The images are very different with, and without the AA-filter.
Without it the images are actually easy noticable quite a lot sharper.
The drawback is of course moiré, and then especially in movie mode.

People do forget that they don't just simply remove the low-pass filter from the sensor. Sure you could manually remove the filter yourself, but it would be rather different, because they replace it with other more essential filters, like IR etc.

I do believe there was someone who did upload stuff about his own project wtih the 5d mk3 where he actually removed the filter manually. The images he posted did show a very noticable difference in sharpness. Try look it up.

The removal of the entire low-pass filter is something that is common process to create IR-cameras though

1. Just count the stop differences, and you have it.

2. Personally I try not to go over 1600, but I am sure that others might find 3200 perfectly acceptable.
(Drop by your local camera store, and take with you your k20d, one of your own lenses, and do comparable shots to find out what you would think personally.)


When it comes to the Northern Lights, it is tricky really. It depends on its speed and intensity. You also have to think what you want out of the image. If you want high details on a fast moving light, you really would benefit a lot from a quick shutter and bright glass. (Think timelapse.)

I soo want to convert a Tokina 11-16mm f2.8 for stuff like this

Tip:
Check out Ole C. Salomonsen's work regarding this subject.

I figured I wanted to try a m50 f1.7 on the k-5 for some astro shots.
Turned out it was not the best idea. The lens picks up the slightest light as massive flaring.

This got me thinking.
Using the original lens hood will not be very effective, so it would be better if I designed a new one instead.

I was not able to find the original lens design information for the lens, so maybe O'Connell's work could be sufficant for it.

Anyone able to correct me on this base data, is something wrong?




Most likely I will do a step-down before the actual lens hood will come.
How will it be when thinking about flare to lets say: 67->49mm -> (CPL) -> further step down -> hood.

If cost is hard to justify I would not even consider the K30.

I was quite recently in the same pedicament that you are in now.
Below 50mm, I only have my old Zuiko 21/2 lens, and wanted something for walk-around.
Since I do venture a lot above the arctic circle, 3.5 is a tad bit slow, when the sun never shines. That is the only reason I scratched the k28/3.5 from my list.

The k30 I did keep a track on however. I even spoted it on a few auctions, but it was the same thing again, and again. Like 5 min before it closed it was around $120, but never ended below $305. Just a reminder if you consider cost a big issue.

For my own cause I ended up finding a deal on a RMC Tokina 28/2.8 for £12, and it have served me well so far. Works quite nice even wide open. I have yet to get a chance to test it extensively though, but hopefully I will soon enough take another trip above the arctic circle and find out.

If you use the focal length a lot, for stuff like street, I would probably advice you to keep an eye out for the F28.

I did another shoot yesterday of another game, and it went a lot better.

For that lens all the aberration issues were gone by f5.6, and the lighting was quite different, so it still kept me on 125-320 iso in TAv.
And I remembered my CPL

I just played a bit with it in LR 4.1, and the pink seems to be okay corrected by the 'tint' stuff in the WB feature. I had not thought about the tint thing.

The feature of colour fringing does help a bit. Nice idea, but it is rather limiting. And the CA button is just partially helping.

Are there ways in PS (6) to do this more detailed, and to a localized region?




Does anyone have any greater experience with this lens?
It would really be nice to know what apertures I need to use, and at what range, to avoid CA as much as possible.

[edit] In retrospect I wish I had brought a CPL with me that day, but the lens is soo annoying to use with a CPL when I use the original hood with it.

(The images have just been opened into Photoshop, and croped, then saved to jpg. Nothing have been done to them.)

The white have gone all pink on me here. This was a big issue in some shots, because one teams cloths had a lot of white in them.


iso 200 : 120mm : f4.0 : 1/500s

The edges here just screams at me. And the white is still rather pink.


iso 640 : 150mm : f4.0 : 1/500s


Just for the record. The conditions was insane that day. From bright sunlight on half the field, to full overcast, rain, wind, and then to gleamy sun on one third of the field.

Hello.

I am rather new to the digital stuff when it comes to photography, and have come across some issues I was wondering if anyone had any suggestion on how I could correct.
Tips on how to avoid it by using different settings, or how to correct it in post by either Lightroom or Photoshop, are both welcome.


Shot with: 'Sigma 50-150mm f/2.8 II EX DC APO HSM' on a 'K-5 (1.13)' in 'TAv' with 'Cloudy WB' and full quality 'DNG' files.
I do not believe I used any EV correction on those two examples, might be something someone could come with suggestions for if it would help.

(The idea behind those settings was to freeze the action with the shutter speed, and I thought f4 was enough on that lens to get ride of most of the CA, while still keeping iso fairly low. WB just landed on cloudy since it was partially cloudy the day, and I wanted to get a relatively okay instant review without having to force the camera to do auto.)