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Fun with the 645D
- Thread starter tsjanik
- Start date
Tsjanik, Nice photo. Good to see a new post. I also shoot with the 645D and 35mm A. I'm often in the UP of Michigan at Pictured Rocks and have Lake Superior in the photos. I was wondering how you correct for the barrel distortion of the 35mm A. Are you doing this in Lightroom, Photoshop or something other? What settings? Thanks. And again, good work.
Shashin
Well-known member
Tom, I am enjoying the Pentax color. And you are right about how much you can push these files around.
I really enjoy these "out of season" photographs. It really emphasizes the palette the world has. We are kind of blind to it--if it is mud, it must be blah. I just love the water, sand, and sky color/texture you have in that image.
I really enjoy these "out of season" photographs. It really emphasizes the palette the world has. We are kind of blind to it--if it is mud, it must be blah. I just love the water, sand, and sky color/texture you have in that image.
Tom +1! The tonality of your image as others have pointed out is simply fabulous as is the image itself.
Agree with your assesment that the 645D's files are very maliable in post processing.
Dave (D&A)
Thanks everyone. Wildrover: no correction applied here. I have seen a slight barrel distortion in the 35, when stitching, but I have never applied any correction to a single shot. Shashin: it was blah as you say, the only reason I got this shot is a self-imposed assignment to print a picture every day for a year. That project forced me out of the house.
Unrelated but interesting is this size comparison:
Compare camera dimensions side by side
Unrelated but interesting is this size comparison:
Compare camera dimensions side by side
Tom,
I think why you posted image (above) works so well (for me), is the various richness of textures of the sky, land and water you were able to bring out. It's that and also these "textures" are all running horizontal. Reminds me a bit why some are facinated when different color sand is layered on top of one another in a bottle. It's as though each of your elements is layered one on top of another but yet are all still recongnizable for what they are.
Interesting size comparison. With the height and width of a sensor (not depth) primarily related to it's mass and size, I wonder how they were able to stuff that gigantic sensor of the 645D into it's smaller body? (relative to the size of the D3x)
Dave (D&A)
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Shashin, I found a few shots that show the slight barrel distortion of the 35mm A. I worked on them a bit to make them presentable, but I didn't correct for the barrel distortion I'm seeing. Normally, I would have added a +5 correction in Lightroom 3. In most shots you wouldn't see this, but with a long unbroken horizon line where sky meets water, it's more apparent. I brought up the question because I was wondering how other folks correct for this. All in all, I'm very happy with the 645D and 35mm A combination. Receding Memories was in Door County, Wisconsin and the other two were in Pictured Rocks National Lakeshore in Michigan's Upper Peninsula.View attachment 54385
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Richard, your images are a reminder of some of the unusal and dramatic shoreline scenery I saw when traveling north of Michagan's upper Peninsula well into Canada. The weather was moody and it closely matched the rock formations as I traveled up the main highway. Lovely images!
As for the barrel distortion seen in the 35mm A lens, I have just a little experience with this lens as opposed to lots with its autofocus counterpart (many samples tested). What is interesting is the FA 35mm f3.5 has very unusal and strong field curvature, and with some subjects can be readily seen. Yet, this field curvature doesn't seem to play a prominant role in barrel distortion when shooting subjects at close and moderate disatnces (as these flat field images stay relatively flat). At infinity and towards the sides/edges of the frame, the curvature can be readily seen as the focus plane is different on the sides vs. the rest of the image. It appears the manual focus version of this lens has far less field curvature, but may not be quite as sharp a lens towards the central part of the frame when compared to the FA 35mm f3.5 . It may have been a design tradeoff by Pentax.
Often I've seen other examples with some 35mm format wide angle lenses that when subsequently updated, field curvature increased, which was a consequesnce of increasing the lens's resolution.
Dave (D&A)
As for the barrel distortion seen in the 35mm A lens, I have just a little experience with this lens as opposed to lots with its autofocus counterpart (many samples tested). What is interesting is the FA 35mm f3.5 has very unusal and strong field curvature, and with some subjects can be readily seen. Yet, this field curvature doesn't seem to play a prominant role in barrel distortion when shooting subjects at close and moderate disatnces (as these flat field images stay relatively flat). At infinity and towards the sides/edges of the frame, the curvature can be readily seen as the focus plane is different on the sides vs. the rest of the image. It appears the manual focus version of this lens has far less field curvature, but may not be quite as sharp a lens towards the central part of the frame when compared to the FA 35mm f3.5 . It may have been a design tradeoff by Pentax.
Often I've seen other examples with some 35mm format wide angle lenses that when subsequently updated, field curvature increased, which was a consequesnce of increasing the lens's resolution.
Dave (D&A)
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Shashin
Well-known member
WildRover, I am not sure what you are seeing, whether it is optical or a property of the horizon--the horizon is an equidistant line rather than a line that gets further away toward the edges of the frame like those on buildings (and I have no idea if that makes a difference, but I have had problems with horizon lines looking crooked after leveling the camera). Here is a shot I took recently with the A 35mm in Tokyo that has a lot of straight lines. I am not seeing barrel distortion, at least nothing that stands out.
http://forum.getdpi.com/forum/370730-post7853.html
Beautiful images, BTW.
Shashin,
I just had a look at the link to your posted image. Towards the top of the image, I do see mild barrel distortion, mainly observed on the upper two tiers of the building. It's quite readily seen in my opinion although I realize the camera was probably pointed upwards for the shot. Easily correctable in post processing though.
Dave (D&A)
I just had a look at the link to your posted image. Towards the top of the image, I do see mild barrel distortion, mainly observed on the upper two tiers of the building. It's quite readily seen in my opinion although I realize the camera was probably pointed upwards for the shot. Easily correctable in post processing though.
Dave (D&A)
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Those are really nice; few realize how lovely the Great Lakes are.
Thanks for the comments guys. Lake Superior is a special place. Lots of parks and undeveloped public lands. I did a couple circle tours thru Canada years ago. There is so much variety in the Lake Superior region that it can keep one busy indefinitely. I am planning a trip soon to try and catch a bit of winter. Also a trip to the southwest in Spring. I've accumulated a fairly extensive assortment of lenses for the 645D - A, FA, 67, but haven't tested or used many of them yet. If I get something interesting from my upcoming travels, I'll post a few. Maybe something from each of the lenses. I do plan on getting the 25mm when it becomes available. That lens seems to have a fair share of chromatic aberration and it will drive me nuts. The possibilities with such a lens though are so great that I will have to accept its flaws and try to fix as much as possible in post.
WildRover, look forward to future image postings. Like others, I've heard the new 25mm is exceptionally good. Excellent sharpness with some edge/corner softness at the wider apertures but sharpens up across the frame when stopped down.
As for CA, I too have seen a fair number of images illustrating the fairly high levels. I thought this was a bit surprising, especially that the lens is a new optical design. Still all things considered, its a very interesting lens and I too hope to try one out in the not too distant future.
Dave (D&A)
As for CA, I too have seen a fair number of images illustrating the fairly high levels. I thought this was a bit surprising, especially that the lens is a new optical design. Still all things considered, its a very interesting lens and I too hope to try one out in the not too distant future.
Dave (D&A)
