Why does my camera make a whirring noise during a long exposure?

Question

I have a Sony Alpha a55.

When I take a long exposure photo, while the shutter is open, the camera makes a whirring sound. What causes this noise and why is it necessary to the camera's operation? (I have interface sounds turned off — so I suppose this is some piece of the hardware physically making a noise.)

Asked by jtbandes

Answer

I'm familiar with Canon lenses featuring Image Stabilization that can emit a faint "whir" as IS operates. Your Sony body has a form of image stabilization built into the body, and if that's on during a long exposure, you might be hearing that as it operates.

If you're shooting long-exposure shots with the camera mounted on a tripod (which would be best), it's usually recommended that image stabilization be turned off (I believe this to be the case for your a55).

Answered by D. Lambert

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What do Pentax, Sony, and Olympus DSLRs offer that differs from Canon and Nikon?

Question

We have a question and answers outlining the significant differences between the "big two" DSLR brands. I'm interested in the other DSLR makers, and how the cameras they make compare in terms of significant features, system design philosophy, and unique or interesting photographic capabilities enabled or made easier by these cameras. Likewise, what such things are not handled as well?

Take "the big two have more market share" and the associated advantages of availability, accessibility, and third-party support and documentation as a given.

I'm not interested here in compact cameras, interchangeable-lens cameras with electronic viewfinders, or in rangefinders.

I know Olympus is primarily focused on the mirrorless Micro-Four Thirds, but they still have current models in the E series. Likewise, while Sony seems focused on the pellicle-mirror SLT line (which uses an electronic viewfinder), the a900 is still a traditional DSLR.

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P.S.: Differences in lens lineups are covered at How much do lens lineups vary across platforms?

Asked by mattdm

Answer

As these camera makers own a smaller market share than Canon or Nikon, they have often tried more radical and innovative approaches than the big two. You can see both Canon and Nikon as more traditional makers with very consistent and proven features in their cameras.

• When Sony bought Konica-Minolta's camera division, they inherited the only body-based stabilization system which they currently use in all their DSLRs and SLT cameras. Pentax and Olympus actually followed with their own version of the same.

• In-body stabilization is the most significant difference between these brands and the big two as it stabilizes all lenses at no additional cost. There are some discussions regarding which type of stabilization is better but this is not only a cost saving feature (since you do not have to buy stabilization which each lens) but also an enabling feature since plenty of lenses have no stabilized equivalent (such as bright short primes and fisheyes).

• Pentax goes one step further by using a magnetically suspended sensor and lets it rotate as well as shift. This gives them the unique ability to automatically correct for camera tilt (up to 2 degrees) and they can also shift the sensor to change perspective right in the camera. The just-announced mirrorless Olympus OM-D E-M5 will also be able to rotate its sensor.

• Partly due to their smaller lens lineups, Pentax and Olympus have a smaller foothold in the pro market and therefore have developed fewer very high-end features including high-speed autofocus and continuous drives. The only DSLRs to shoot at 10 FPS or more are from Canon and Nikon. High-end Canon and Nikon cameras have more autofocus points than those used by Pentax, Sony and Olympus. Sony is on the fence here as having the only full-frame cameras among the smaller three manufacturers and their SLT models do shoot faster than 10 FPS.

• Pentax builds some of the toughest DSLRs around and have the only ones rated to work below freezing (down to -10C or 14F). They have also introduced weather-sealing in their mid-range DSLRs along with matching lenses. With the Canon and Nikon, you need to buy rather expensive cameras and quite expensive lenses to get a weather-sealed system.

• There are also different design philosophies among all manufacturers which is partly due to their target audience but also part of their identities, meaning sometimes something is done differently just to be different, not to be better. For example, Nikon lenses and dials rotate in the opposite direction as all other brands (although the dial direction is reversible on mid-to-high end models).

• Pentax has the easiest cameras to use and theirs work in a very thoughtful way. For example, when using the 2s or 3s-Remote timer, Pentax DSLRs automatically perform mirror-lockup (MLU) and disable image stabilization. This is exactly what is needed when working from a tripod and takes more steps to do in other systems.

• Sony DSLRs tend to have fewer features. While covering all the basics, they tend to be less customizable. Olympus on the other hand provides a high-level of customization even in entry-level models.

There are certainly tons of other design and feature differences which will be more or less significant depending on the type of photography you do. Particularly when it comes to flash and studio work.

Answered by Itai

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“One size fits all lens” for Sony and Nikon, or a Nikon lens plus adapter?

Question

I've been taking photos with the supplied kit lens with my Sony Alpha 200 for the last couple of years. I'm looking at changing the body to a Nikon D7000 at some point in the future and I'm also looking at getting a 50mm prime lens.

My question is, which lens can I buy that would fit a Sony Alpha 200 and also a Nikon D7000? Should I get a Nikon lens and a lens adapter or is there some form of 'one-size-fits-all' lens?

Asked by Anish Patel

Answer

There is no such thing as a universal lens. The shape of the connection, position of the contacts (and electric protocol too), distance between the connector and sensor are all different.

There are adapters to bridge the gap which are mostly used for legacy lenses. The reason is that with those adapters you will lose most communication between the body and lens, so you have to focus manual, probably have to set aperture manually and sometimes will have to use the camera in Manual mode only (no metering).

There two extremely important points to note above: - If the lens you use (such as ALL kit lenses for DSLRs) does NOT have an aperture ring, you will only be able to shoot at one aperture (usually either the smallest or the largest). - If you adapt a lens who is supposed to sit closer to sensor, it will be be able to focus very far and you will almost certainly lose infinity focus.

Given all this and my understanding that your lens investment is minimal, I would recommend simply buying the lenses you need for your new camera.

Answered by Itai

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Does the Sony A77 have a shutter?

Question

I bought last month the new Sony A77 and I am so interested to learn about how its translucent mirror technology works but couldn't find enough information on it.

My question is does it has shutter? If it does is that shutter really mechanical and moving 12 times in 1 second?

Asked by shobani

Answer

Yes, the A77 has a mechanical shutter and it does move at 12 FPS per second. There are a number of cameras with similar shutter-speeds including some ultra-zooms but indeed this is very fast.

What it does not have is a motor to move the mirror. This is more problematic for speed then the shutter itself since a mirror is heavy and has to move out of the way completely and back that fast.

Instead it has semi-transparent mirror (transluscent is not the right word technically). The mirror is made of flexible material that reflects about 30% of the light and lets the rest straight through. This makes the imaging sensor have to work a little harder but the autofocus sensor more so.

Answered by Itai

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What 3D lenses are available for a Sony NEX camera?

Question

I currently have a Sony NEX-VG10. I would like to know if it's possible or worthwhile to get a 3D lens for it? I did a google search and can't seem to find any — or am I blind?

Answer

It's certainly possible; your camera has E-mount; you could use adapter for A-mount lenses together with a 3Dstereo lens. Perhaps slightly more known is Loreo 3D lens, that comes in Sony/Minolta A, Canon EF, Nikon F or Pentax K mount and could be used with adapter for that mount. Or, you could combine an adapter for four-thirds and Panasonic 3D lens.

As for if it's worthwhile - only you can decide that. You can search for results others have achieved and think if it could be a worthy addition to your images/videos. Some find that a special camera (such as Fuji FinePix Real 3D W3) does the job better, mostly because the distance between lenses is closer to human vision, you have live preview of the result, control over zoom and aperture, and you have full resolution for both images.

For 3D photos of still scenes, an alternative is to attach your camera on a focusing rail on top of a tripod so that it can ride sideways, and using manual mode and manual focusing (for making sure nothing changes between frames) to take separate frames for left and right image, and post-process them into a 3D image.

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What happens when a Sony SLT camera is operated with mirror up?

Question

What happens if you attempt to operate a Sony SLT (pellicle mirror) camera with the mirror up? Does the camera detect this condition? Will the camera shoot? What happens to autofocus--can the camera fall back to contrast detection? Is the increase in exposure value accounted for?

Answer

The SLT-A55 at least no longer focuses but everything works, even with the mirror removed which you can do without too much difficulty. Exposure is off by about 1/3 EV.

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What is the DT series of Sony lenses?

Question

Among the Sony lenses there are some types with a DT abbreviation and some are without it. Those having DT called DT-series.

What does DT mean? What is the difference between DT-series lenses and the rest of Sony?

Answer

DT (Digital Technology - source) means that the lens is designed to work with a cropped sensor camera. It should not be used with a full frame sensor or 35mm film. If you use it with a full frame sensor then some of the image would be black, particularly towards the corners, as the light projected by the lens would not cover the sensor.

Having a smaller area to project light on to means that lenses can be smaller, lighter and are generally cheaper. However if you later upgraded your DSLR body to one with a full frame sensor you would have to replace the lens.

Similar questions:

• What is the difference between EF and EF-S lenses? (Canon)
• DX or FX lenses ? (Nikon)

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What is DT series of Sony lenses?

Question

Among the Sony lenses there are some types with a DT abbreviation and some are without it. Those having DT called DT-series.

I didn't manage to find out what does DT mean. Could you help me? What is the difference between DT-series lenses and the rest of Sony?

Answer

DT (Digital Technology - source) means that the lens is designed to work with a cropped sensor camera. It should not be used with a full frame sensor or 35mm film. If you use it with a full frame sensor then some of the image would be black, particularly towards the corners, as the light projected by the lens would not cover the sensor.

Having a smaller area to project light on to means that lenses can be smaller, lighter and are generally cheaper. However if you later upgraded your DSLR body to one with a full frame sensor you would have to replace the lens.

Similar questions:

• What is the difference between EF and EF-S lenses? (Canon)
• DX or FX lenses ? (Nikon)

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What is a good 360 degree camera?

Question

I want to buy a new camera for a 360 degree shoot , so can anyone suggest me the good one

I have seen that Sony Bloggie camera which has 3D camera and a 360 degree lens too, so does this camera have good quality to take 360 photos?

Link to Sony Bloggie Camera

Answer

From what I have read, the Sony Bloggie has quite poor quality and is pretty limited as far as what you can do for 360 degree photography. It is more of a market gimmick then a full fledged option. The camera only starts with a 5MP sensor, and stretching that out over a very small sensor, and a very very large aspect, you can only imagine that it isn't setup for serious use.

Some opinions from reviews:

• The 360 degree attachment is great as a novelty item but you won't want to take serious video with it(link).
• While 360 degree mode is more a toy than premium class, you get good casual takes. Funny mode to play with. (link).

You might want to take a look at pano-pro if you want to get into this field.

I found a pano photography forum that has greater expert advice on using this camera in the real world here: Link

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What should I do to switch my gear from Sony to Canon?

Question

So I currently have a Sony A700 which i bought a year ago, and wanting to get some quality glass. I was looking at the Carl Zeiss 24-70/f2.8 lens, but then got talking to a friend who's a canon user.

He raised some good points about Canon vs Sony, namely: - Availability - second hand gear, hire gear, borrow, etc - Repairs - if my camera breaks when i'm in the Amazon jungle, much better chance of finding somebody to repair a canon than a sony

I'm totally happy with my Sony A700, however if i'm going to be spending $2000 on some quality glass, i'm starting to think maybe i should spend some more and get Canon quality glass (along with a canon body of course). I could sell my Sony + lenses and recoup perhaps 1/3 of the cost of the new kit, a little less than the extra i'll be paying for a new body, so really what i'll be losing out of it is the extra sony lenses i have, but gaining a kickass new body, a killer lens, and a new more widely supported system.

If i do this, i'm thinking the 5D (either second hand, or a new Mark II).

My question is, for all your experienced photographers/ enthusiasts out there, what would you do if you were in my shoes?

Its a tough choice, as was my original choice to go with sony (which I am now slightly regretting).

Cheers, Greg

UPDATE: Thanks for an excellent discussion everybody, i'm glad i stumbled across this site the other day. All things considered, i'm leaning towards cutting my losses and switching to Canon before i have even more invested.

I figure if i can sell my sony kit (which i've spent about 2.3k on) for about 1k, then for a 5d mk II with 24-105 lens i'll be out of pocket another 2.4k. That gives me an amazing body, video capabilities, a great versatile pro lens, and the advantages that canon has over sony.

on the other hand, if i stick with sony, i'm looking at spending about 1.7k on their 24-70 carl zeiss lens. that's a saving of around $700, but i'll still be on a partial frame camera, and still have the pitfalls of a smaller user base and less gear availability. I think now is a good time for me to switch... it feels like the right thing to do.

Thanks everybody for your advice... i'm very surprised to have seen such level-headed arguments about brands... amazed in fact. Nobody bashed another brand, at all, which is really refreshing.. i can see the value of sony and carl zeiss (reading reviews it seems there 24-70 is best in class lens, as are their new primes), however they just dont have the market penetration i'm craving.

I still have a little while before i part with my cash, so will be partaking in further discussion here if there is more, but if not i'm happy with what i got from it. you're all fantastic.

Cheers Greg

Answer

I don't have specific Sony experience, but I'd suggest getting over the doubts. There's a number of reasons for this:

1. Sony bought Minolta, a camera company, and thus bought into the Minolta legacy and their glass. In other words, your friend isn't correct, there is a lot of Minolta gear on the open market and much, if not all, will work on a Sony.

2. When it comes to second hand, legacy, gear the only company that will better Sony in support (and that may be debatable) is Pentax. Like Pentax, Sony has shake reduction on the body and that means old glass will benefit and there is some truly great optics out there for peanuts.

3. Sony is a massive corporation, you can get gear repaired by them, they're everywhere. Bear in mind that a dSLR is an electronic device and Sony is the king of electronics. Frankly I'd expect it to be easier to repair Sony, they have their own stores after all, the only camera maker that does. Besides, a close friend with a 7D got to spend more than 3 weeks with film when his 7D was in for repair with Canon, not exactly speed service there, so I wouldn't assume that you gain anything from Canon on this front.

4. Zeiss glass will equal or exceed lenses made by Canon. We're talking one of the best lens makers on the planet with Zeiss.

5. Sony makes more than 50% of the worlds sensors, including sensors for Nikon, Pentax, and others. Simply put, if you aren't shooting Canon, you're very likely shooting a Sony sensor. Does it mean anything? Well, cameras making the most buzz about things like high ISO with low noise carry a Sony sensor.

6. Like Canon, Sony has full frame options and they're very well priced and well reviewed.

Now, after all that, Canon makes an excellent camera beyond question. They have great lenses, strong support, and their image IQ doesn't give into others. So, if you do cave in and go Canon, I'm sure that you'll be happy with them. However, I think you'll also find that you really didn't gain anything over Sony with a comparable camera.

That's my take, in any case, and I'll be curious to see what others think. For myself, I can't believe I just defended Sony!

By the way, the question is subjective and that may get it shot down but I didn't vote for that because I think it's worthwhile to have people ask some of these questions. There's a weird brand loyalty in the camera world that goes a little beyond the rational sometimes and so it's worthwhile for us to have some discussions that maybe challenges those beliefs a little bit. After all, it's a photographic tool, not a life partner... :)

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Can I charge a Sony Cybershot DSC-T200 using a computer's USB port?

Question

The Sony Cybershot DSC-T200 comes with an external wall mounted charger for its proprietary battery. Some Sony cameras allow you to draw power from a computer's USB port. Is this possible with the DSC-T200?

Answer

According to Page 35 of the manual, the battery can only be charged in the charger, not in the camera.

(note: the linked manual says DSCT70.pdf in the link, but the manual covers 3 versions including the T200).

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How should I decide which flash to purchase for my Sony A580?

Question

I have a Sony a580 and I'm thinking about purchasing a flash.

I'd like to use the flash for indoor photography: portraits, group photos and candid shots.

It looks like there are a number of options out there with wildly different prices (from $100 up to $500). With those price differences you have to ask if it would be better to purchase multiple cheaper flashes than one of the high end units.

What factors should I consider when making this decision?

Answer

Probably the first important decision is whether you need the convenience (and working speed) of TTL metering with a flash, or are you going to set up your shots in a more crafty way and so a (significantly cheaper) manual flash would suffice.

You can probably get away with a manual one for portraits and group shots (actually, it would be better to have at least two, so you'd have a key light for lighting the scene and a fill light to reduce shadows from the other side). Opportunities for candid shots, however, may come unplanned, and TTL would be of great help for making sure the flash gives the right amount of pop in hurry. Perhaps one TTL flash and one manual flash to help in off-camera work would be a good starting setup for you.

Note that Sony/Minolta hot-shoes are different from ISO 518 standard hot shoe that the rest of manufacturers use, so you'll need an adapter for most manual flashes if you want to use them on-camera.

Further factors to consider, no matter if you want the TTL or not, are still the same as when choosing a manual flash.

You'll probably also need some accessories for your flash - see "What's a decent lighting kit for getting started with portraits?".

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Should I choose a Canon 550D or a Sony DSLR-A580?

Question

I am planning to buy a Canon EOS 550D with its Kit Lens (18-55 mm) and a prime lens (50 mm 1.8) with my main intention of clicking portrait and landscape pictures. Just yesterday I came across Sony DSLR-A580 and noticed that the features were a bit better for the Sony as compared to the Canon. I referred to this link to understand the ups and downs of both the DSLR's. I have personally used the Sony A580 (with prime lens 50 mm 1.8 and telephoto lens Sigma 18-200 mm) for more than 3 months and I am quite impressed with the quality. I have even used the Canon 550D in stores to get a feel for the quality and in stores I felt Canon was better. I understand that Sony would be a bit more expensive than the Canon with the same setup, but is there really that much of a difference in quality of images and video?

Answer

There's no single answer to this question, because it comes down to a lot of personal factors. However, you won't go wrong with either choice. I highly recommend looking at How much do lens lineups vary across platforms? and considering which system might fit your vision of your working style as a photographer — but not stressing about it too much.

The difference in image quality in an absolute sense is very small. That's because all modern DSLRs offer excellent, amazing image quality, and any debate is between levels of A-grade. These differences are magnified because camera review sites wouldn't get very many hits if they just kept focusing on that positive story — instead, they have a huge incentive to magnify small differences into distinguishing factors.

The Snapsort link you gave provides a good example of this. While Snapsort provides some useful comparison information, one thing it says is that the Sony camera provides "More than 20% better image quality". This is clearly preposterous. The numbers they use — given as the bare "80.0 vs 66.0" — are from some highly-technical sensor measurement scores, which demonstrate some small clinical aspects of image quality, and which barely relate in any way to the actual potential quality of results.

The claim that one model "Distinguishes more than 3x more colors" is also absurd — there's a technically-measured bit depth of "23.8 bits vs 22.1 bits", which both does not correspond usefully to the practical dynamic range of the sensor nor have anything to do with "number of colors distinguished". The higher value is better, but when it's presented as "3× better" that sounds like a big deal — when in reality, it's a difference that humans, even expert humans, can't possibly distinguish without taking careful measurements.

So, yeah. Don't worry too much about these things.

That's assuming there's no deal-breaker lack of functionality for you in one model or another. For example, if you absolutely must have 24p video for a project, this particular Sony model won't do.

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Is there any difference between the Sony A65 and A55 other than megapixels?

Question

When I look at dpreview's side-by-side camera comparison page, there is no difference between two cameras except pixel count (24MP vs. 16MP).

If that's the only difference then $200 isn't worth it for just more pixels, because I don't need them. Is there anything else?

Answer

I can a spot a few differences; 24 fps video vs 30, more WB settings, different battery (longer lasting), heavier and bigger but thinner body (probably easier to hold), extra connectivity options, ±5 EV (at 1/3 EV steps) as oppose to ±2 EV (at 1/3 EV steps), AE bracketing option.

The Sony SLT A77 seems like a better alternative though.

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Is it possible to control my Sony Alpha 550 from my computer?

Question

Is there any way for me to connect my Sony Alpha 550 Digital SLR to my computer so that I can, for example, view live view images on the computer screen, control the settings using the computer, or even set up timed photos?

Answer

No, except for the Live-View part.

For that you would need a HDMI capture device with monitoring function.

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How quick are you able to set the exposure on the Sony NEX-C3 (or other cameras like it)?

Question

Background

I am considering the NEX-C3 as a nice camera to take on trips\shoots\vacation\outing\etc where my DSLR would be too large but I do not want to sacrifice my ability to set the exposure of my shots. I know it is possible, but I am concerned how quickly I am able to achieve it.

How can I?

My main flow with my DSLR is to have it set in aperture priority so that the front wheel operates the aperture and the back wheel changes the exposure compensation (+/-). I've found this method ideal since I mostly trust the in camera meter but can quickly change the exposure to taste, all without pressing any buttons or digging through menus.

I know I will not be able to achieve this sort of speed on the NEX-C3. So my question is this, are you able to mimic this work flow without digging through menus or an excessive amount of button presses?

Or is there a workflow on the NEX-C3 that allows you to set exposure in a similar fashion but faster?

So...

I've picked the Sony NEX-C3 simply because it's the newest and has the largest sensor among it's competitors. But, if a competing camera in the same class is capable of doing what I described above please let me know.

Thanks in reading my long winded question!

Answer

On a NEX-camera in Av, the back wheel selects an aperture unless you press "up" (on the combined d-pad/wheel) which will allow you to change exposure compensation. Not as quick as having two dials, but better than most P&S cameras. You could also configure the center button to allow quick access to ISO and metering mode, without having to delve into the menu.

The focus-peeking feature added in a recent firmware update (should be included from the start with the C3, IIRC) is really quite handy for macro work, since it gives you a nice, solid indication of the current DOF.

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How do I clean dust in a Sony A55 SLT?

Question

I am pretty sure I have dust inside of my Sony a55 SLT (Single Lens Translucent). However I'm not sure how to get rid of it or where exactly it is. I think it could be either on the translucent mirror or the sensor itself. It's in the same place each time, but mostly occurs on images with a high f number (e.g. F22 etc)

An example image (cropped):

Would a general sensor cleaning kit remove the dust form the translucent mirror part?

I'm unsure of what to do as it's not a conventional mirror like in SLR cameras.

Any recommendations on a good cleaning kit? To be honest I'm slightly scared about it all as I don't want to destroy my camera!

Answer

You have dust on the sensor. The higher the F-stop the more noticeable they are.

To get to it you have to release the small latch at the base of the translucent mirror and lift it manually.

If that happens rarely, I recommend you have it done in a store. The charge about $25 and they have a lot of practice doing it. Some stores here even do it for free if you bought the camera there.

The other option is to do it yourself using a wet-clean solution. The one I use is from VisibleDust. You need to buy a small bottle of liquid and some compatible swabs. The swabs get used once and are disposed of after. One set of swabs plus liquid cost about $80. You'll be able to clean a dozen times or so with this.

Avoid using a blower, compressed air or anything similar. It usually only puts more dust on the sensor, even those with filters on the intake are only marginally better.

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Can anyone recommend a telephoto lens for a Sony DSC-H3?

Question

I have a Sony DSC-H3. I'd like to buy some new lenses for it for experimentation purposes. Specifically, I'd like to get a telephoto lens. The only issue is, I can't figure out which one to get. The official Sony one has been discontinued, and I'm seeing conflicting reviews for a few possible candidates on Amazon and Ebay.

Does anyone have a suggestion for a telephoto lens?

Thanks,

Answer

The Sony DSC-H3 is a superzoom camera with a permanently-attached lens. You can't really get new lenses for it in the same sense one might with an interchangeable-lens camera. There are some things sold as telephoto lenses for such cameras, but really they are "teleside converters" — secondary lenses which attach in front of the permanent lens. I don't have any specific purchase advice, but will note that such a lens is likely to add aberrations and reduce sharpness, particularly if it's cheap. You might get okay results, but you might actually do just as well by just cropping and enlarging.

If you're seriously interested in getting some new lenses for it for experimentation purposes, I highly suggest you start considering an interchangeable lens system — either a DSLR or one of the new mirrorless camera systems like Sony's NEX. This will have more sticker shock, but if you really want to experiment with photography, you're going to want something like that eventually anyway. Might as well start sooner rather than putting money in a different direction.

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Is there a way to make auto-focus more smooth while filming with Sony A55?

Question

Wondering if anyone can help with this. I have a Sony SLT-A55, and when in video recording mode it is able to auto focus.

My issue is that it does this "too quickly".

For example, if I'm shooting something and I'm panning across, following a subject, if anything passes close in front of the camera for even a second it will try to focus on that, then will have to refocus on the subject I was following. This causes a really annoying focus-loss effect on the video. To give you more of an idea as to whats happening the following link shows an example. You will notice that it loses focus half way through. This can happen multiple times so it becomes really noticeable.

http://www.youtube.com/watch?v=6UwvjMiNwH8

So my question is, how can I prevent this, without having to go into full manual focus mode? From research I have found out that lenses are available with focus hold buttons — would getting a lens with this help? Would I have to hold the button down the entire time during which I don't want auto focus, or would it be a toggle style button?

Is there anyway I can prevent this? Slow the focus when the subject goes out of view? Buy some sort of better lens?

Answer

Focus hold buttons, from my understanding, just disengage the autofocus and 'hold' the focus where it currently is, not on a moving subject - so pressing this will not create a kind of 'follow focus even if you can't see the subject' scenario.

I don't think you're going to find any way around this, except for manual focusing- the camera literally can't see the subject when it passes it behind the object. You could use another camera with worse video autofocus like a Nikon D3100, D5100, etc but I have one, and the video autofocus is TERRIBLE. Its noisy, super slow, unpredictable - I'd not recommend it at all.

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Canon SX230 HS or Sony Nex 5

Question

I have a Canon SX230 HS. It's a good compact camera but I would like something better.

Do anyone advise me to upgrade my camera to a bridge Sony Nex 5 or it doesn't make sense?

Should I buy a reflex without pass through a bridge?

Answer

Those two models are very different types of camera:

• The SX230 is a compact travel-zoom. It has lots of capabilities (including 14X optical zoom) in a small size but its image quality is relatively low. This won't show much in bright daylight and small prints but when shooting indoors and in low-light, quality drops significantly.

• The NEX 5 is a interchangeable lens camera which lets you use different lenses which you must buy separately. The main advantage is that it uses a large sensor, like a DSLR, so it gives very good image quality. On the other hand, it is much more costly. Compared to the SX230 is will be quite a bit bigger when you include a comparable lens.

Right in between you can find a compact camera like the Nikon Coolpix P7000 which uses a larger sensor than the SX230 but smaller than the NEX 5. Image quality and price will be in between the two. The P7000 also has plenty of controls and is more efficient to use than both the models you are considering.

Finally, if you want high image quality and speed, you have to consider a DSLR. The obvious thing to consider is would you get tired of carrying something that big and heavy? That is why a lot of DSLRs get left at home and people buy a second small camera.

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