[rparmar]

My originals are tack-sharp even if they don't appear that way here. And the apparent colour/sharpening noise seen on the 100% crops are also hardly as visible as they are here.

I think this will depend on your colour profile settings and whether you use a browser than respects them. This affects more than just colour I have found, since at high magnifications the sharpness depends on boundaries between pixels and colour differentiation. That's my theory anyway.

But great shots and this is a fantastic lens, especially for a "consumer" product that covers such a wide range.

[rawr]

I don't have this lens, but in order to get the best sharpness out of it, it is useful to look at a few tests or reviews - eg

Pentax SMC DA 55-300mm f/4-5.8 ED - Review / Test Report

to get familiar with how it performs, and what settings get the best out of it.

For example, in the case of the 55-300, it looks like if you want the best resolution/sharpness out of it, stop it down to f5.6 or f8, or f11 as the focal length increases towards 300mm. Also note that the resolution is very good all the way up to 200mm but then drops away somewhat at 300mm.

[Ash]

For example, in the case of the 55-300, it looks like if you want the best resolution/sharpness out of it, stop it down to f5.6 or f8, or f11 as the focal length increases towards 300mm. Also note that the resolution is very good all the way up to 200mm but then drops away somewhat at 300mm.

Whilst this is the case for most lenses, some lenses perform remarkably well wide open, and the 55-300 is one of them. I have a number of sharp images from this lens taken wide open, but one must be weary that at that aperture the DoF is very thin.

[BlueBubbleBoy]

First off, let me say thank you for all of the replies! I really appreciate the great responses. I'm making lots of mistakes with my photography so far, so it's nice to have a place to get some advice from other more experienced people.

I'll try to upload some examples tomorrow, I've got just a few minutes to be on the computer right now. I know this lens is very capable as I've seen many great photos on this site using the 55-300 and Ash's examples in this thread too.

From reading the responses, I will have to check to see if I used the 1/focal length rule for shutter speed. That may be part of my problem. I am waiting for the SR to kick in though before I take the picture. I also use the center AF point, focus on my subject in the middle of the frame, then without releasing the half-pushed shutter will recompose with my subject in a different location in the frame. Maybe this is part of my problem? Is it better to select the AF point where I intend my subject to be? If so, when shooting wildlife that could be a little tricky since they don't always want to be so stationary.

BillM mentioned a lens hood. I have not been shooting with a lens hood. I know that helps with lens flare, but does it also help with focusing? I recently just got a hood, so I can start using one now. I also have not been using any filters.

Thanks again for all of your responses and I'll try and get some examples uploaded tomorrow.

B*3

[Ash]

I'm not sure a lens hood will help all that much with focusing, but it does make a difference in image results (limiting flare) in harsly-lit scenes. But your shutter speed is important to take a note of when you are shooting at the high focal lengths.

I'd suggest not recomposing after locking focus given the thin depth of field at high focal lengths that makes it very difficult to keep focus in the right area of the image. Use the selectable focus points to lock focus points then release the shutter as soon as the SR engages without moving the camera (as much as feasible).

[Rondec]

I think the hardest thing about shooting with long lenses is exactly what other said, camera shake. Good technique is crucial to getting a good shot. SR compensates differently for different people. Take some in door shots with varying shutter speeds and see where you are steady and where you aren't. Then, make certain that when you are out shooting that you don't go under that minimum shutter speed.

If you really have concerns about the sharpness of the lens, take a couple of photos on a tripod, using mirror lock up. They should be quite sharp.

Ash is right about recomposing. At 300mm, your depth of field is pretty thin and so if you recompose, you will tend to have your subject move just a little in front or behind your focus point. Better to use the center point and then crop later or, select the focus point.

[dosdan]

As it happens, Falk Lumo discusses SR performance. The conclusion there is that most maker's SR is ineffective at long FL (except possibly Olympus). Once you use a a shutter speed equal to or faster than 1/125s with the K-7, the motion blur performance falls solely back to 1/(FL *crop factor) i.e. the same with or without SR.

See particularly http://falklumo.smugmug.com/photos/837997350_ksmLV-XL.png

Dan.

[Rondec]

As it happens, Falk Lumo discusses SR performance. The conclusion there is that most maker's SR is ineffective at long FL (except possibly Olympus). Once you use a a shutter speed equal to or faster than 1/125s with the K-7, the motion blur performance falls solely back to 1/(FL *crop factor) i.e. the same with or without SR.

See particularly http://falklumo.smugmug.com/photos/837997350_ksmLV-XL.png

Dan.

This work was done using a shorter focal length. There has been a new suggestion that a firmware update has considerably improved SR capability with longer focal lengths based on data from Rudiger (see here). I believe falconeye is currently doing testing on that, so we will see what the new results are, but I can see anecdotally that SR does work for shutter speeds faster 1/125th on the K7, at least.

[BlueBubbleBoy]

After reviewing some of my telephoto shots, it does look like the ones that are the softest are ones where the shutter speed is definitely too slow. One of the reasons for that was that I was shooting in the failing light outside. I guess in that circumstance I would definitely need to be using a tripod. Ash, you mentioned turning SR off and using the 2 second timer when mounted on a tripod. Sorry for my ignorance, but why turn off SR when using a tripod?

I will also make sure to in the future not recompose my shots after locking my focus and see if I see an improvement.

I've attached two pictures. No PP done at all except for 100% crop of both images. I know that they are not perfect exposure-wise (and I realized I accidentally cut off the goose's head in the reflection), but I just wanted to provide a couple of examples.
The goose: 230mm, F/5.6, 1/320, ISO-400, manual
Maybe not too bad, but I may have missed a little since he/she was moving in the water.
The rabbit: 300mm, F5.8, 1/20 , ISO-800, Av priority
I think I now know why I was so off in this one.

I'll try again with my new found knowledge and hopefully post later with some better results. I've got a crazy work week, so it may be a few days before I can get out to take more pictures. Thanks again everyone for the help, and if you have any more suggestions, I'm definitely open to them.

[lescatalpas]

I am a newbe as well, own the k-x only a few days and am experimenting with the 55-300. This picture is uncropped and taken without a tripod. See i have to learn how to put larger pictures here. The source is on the gallery/ nature.

[Ash]

Ash, you mentioned turning SR off and using the 2 second timer when mounted on a tripod. Sorry for my ignorance, but why turn off SR when using a tripod?

SR tells the camera to adjust for small movements in the body only when shutter speed exceeds a threshold around the 1/FL figure. The camera doesn't know it's on a tripod, and so when SR is on in that case, the camera still tries to 'adjust' itself even though it may be perfectly stationary, inducing 'sensor' shake and producing a less sharp result. That's why SR should be switched off.

Also have a look at this thread:
https://www.pentaxforums.com/forums/pentax-beginners-corner-q/98332-image-sta...al-length.html

I will also make sure to in the future not recompose my shots after locking my focus and see if I see an improvement.

And make sure that you are as still as possible once you've locked focus. Technique is vitally important in getting good results.

I've attached two pictures. No PP done at all except for 100% crop of both images. I know that they are not perfect exposure-wise (and I realized I accidentally cut off the goose's head in the reflection), but I just wanted to provide a couple of examples.
The goose: 230mm, F/5.6, 1/320, ISO-400, manual
Maybe not too bad, but I may have missed a little since he/she was moving in the water.
The rabbit: 300mm, F5.8, 1/20 , ISO-800, Av priority
I think I now know why I was so off in this one.

The goose shot looks OK at this resolution, but may even be sharper with revised technique. I don't need to elaborate on the rabbit shot, but in those lighting conditions, there is little you can do to get a sharp shot other than boost ISO to the max, or simply hook the camera up on a tripod and try to get the subject when it's perfectly still for the duration of the shutter speed.

Here is more evidence on SR effectiveness if you're interested:
https://www.pentaxforums.com/forums/pentax-dslr-discussion/91524-shake-reduction-effective.html

[BlueBubbleBoy]

Here is more evidence on SR effectiveness if you're interested:
https://www.pentaxforums.com/forums/pentax-dslr-discussion/91524-shake-reduction-effective.html

Thanks for the links. After doing more testing, it seems to me that I just have really unsteady hands and arms. Even with trying the techniques mentioned, I struggle to get a good crisp image. Here's an example from this evening. When I pulled up in my driveway I saw a squirrel in the yard. I had my K-x with me with the DA L 55-300 already attached. I tried to get a good, crisp shot, but I was just too shaky. I supported my arms on the door of the car with the window down and that helped me get a sharper image. I can't believe I shake like a chihuahua.

F/5.6, 1/320, ISO-800, 210mm
What do you think? Sharp enough or still room for improvement?

[Perrumpo]

Whilst this is the case for most lenses, some lenses perform remarkably well wide open, and the 55-300 is one of them. I have a number of sharp images from this lens taken wide open, but one must be weary that at that aperture the DoF is very thin.

Weary?

I haven't had very good luck with this lens indoors. It's been fine outdoors with a smaller aperture, but most shots wide open aren't sharp at all, even with a tripod. I realize this isn't one of the general characteristics of this lens, but no matter how careful I am to focus (AF is pretty bad, too), they're not sharp. Not sure what else to try.

[Marc Sabatella]

Try posting an example here - maybe others will be able to offer suggestions after seeing what went wrong.

[Perrumpo]

Try posting an example here - maybe others will be able to offer suggestions after seeing what went wrong.

Sure thing. I can't remember if this was AF or manual, but either way, I was getting the same results at 200mm and longer. Sometimes the petals were more focused-looking, but still not sharp. This was on a tripod with remote. I don't think that I simply needed to be further away because the focusing ring was not at one extreme or the other. Btw, my 50-200mm was clear during the same shot at 200mm.



sharp outdoors: