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03-19-2013, 09:27 AM   #16
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What is the widest setting for the bridge camera's lens? I bet it's a number that the ExposurePlot is interpreting as that 40mm spike. Then you have another spike at 27mm, possibly the DA 18-55 at 18mm, which shows up in the Moscow set. The Moscow set has some extra lumps at what would be the ends of each of your lenses in 35mm terms: 27, about 80, 120 and 300. That's fairly common.

The plot won't show you focal lengths you don't have, and it's tough to say how you would use a lens you don't have yet. But if you are using the widest possible setting, something like the DA 15/4 might be perfect.

03-19-2013, 09:55 AM   #17
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QuoteOriginally posted by alexmann Quote
Yeah the tool uses a "35mm equivalent" as a default - I didn't change it for anything, just ran them all through the same settings...does it make a difference?
Well "35mm equivalent" refers to angle of view compared to using the same lens on a camera with a 24X36mm film gate or sensor. With the smaller APS-C sensor it is equivalent to cropping down to the center 75% of a 24X36mm image. Whether that makes a difference depends on how you want to wrap your head around this concept. The angle of view on a 35mm lens used on an APS-C camera is about the same as a 47mm lens on a film camera. But the actual focal length (and image perspective) of the lens is still 35mm in either case.

For me it is like moving between imperial and metric measurements. I just got used to what the relative size, weight, distance, temperature meant in each system and really don't try to translate between the two very often.
03-19-2013, 11:16 AM   #18
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OK, I was just wondering if I should really have used the "real lens length" for the k-m, and the equivalence setting on the pre-DLSR shots to compare the two sets of data....?

To me it's pretty obvious that I'm using both ends of the 18-55 for a lot of shots, and the far end of the 80-200 when I bother using it. That's probably influenced heavily by the lenses I currently have, so the past data (~14,000 shots) may be more relevant...in that case I have "peaks" (>=500 shots) across the range at 27 (11%), 35 (10%), 37 (13%), 50 (4%), 57 (4%), 105 (4%), 374 (5%) & 490 (5%) - which also backs up my current usage and "feel" (when I use the 200 on the zoom, I'd ideally want more...just that's what it goes to!)

So I guess now I know what the majority of my past shots was taken with, what should I go for in 3-4 new lenses? As I'm using the 18mm on the 18-55, and the 27 on legacy was my "wide open" setting on my bridge, I guess I want a nice wide angle lens, then something at the other end, so now I'm looking at the two final ones...what's a good compromise in the 35, 37, 50, 57 range?
03-19-2013, 11:48 AM   #19
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Many folks claim the F 35-70 zoom gives 'near prime' results. I won't say that, but will say I really like mine. The close focus feature at the 70mm end is icing on the cake. This lens can still be had for very little money too.

03-19-2013, 12:02 PM   #20
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The program appears to be looking at the "Focal Length in 35mm Film" data field in EXIF for both cameras, so it's using the same measuring system for both, which is what you want. It's displaying the results in that format too, a bit confusing if you're not used to it but not a huge issue.

You probably should narrow your search a little with budget and the features you think are worth paying for. One example: I have the Sigma-A 50mm f2.8 macro mentioned above. I had a Vivitar 55mm f2.8 macro in M42 screw mount also, both capable of 1:1 magnification, prices pretty close. They look close in image quality, possible edge to the Vivitar. But I found the Vivitar really tough to use because of its mount. I had to focus wide open and then stop down to meter and shoot. It was difficult to use with flash. The Sigma does all that really easily. I can use an M42 lens for other purposes but for macro, I want that extra functionality.

Some focal lengths are not cheap especially for a prime lens. A wide angle prime might take up a lot of your budget. I use a wide-angle zoom (DA 16-45/4) for mostly that reason.

For me, the midrange is easy to cover in primes. Some inexpensive manual focus KA mount suggestions: Sigma SuperWide II 24mm f2.8, Pentax-A 28mm f2.8, Pentax-A 50mm f1.7. The Sigma-A 50/2.8 macro works here, they have a 90/2.8 macro that only does 1:2 that is similar. I think the DA 35mm f2.4 is the best way to get a good 35mm - older lenses are almost as expensive and not as good. Samyang makes an 85mm f1.4 in KA mount, sold under about 5 brands.

Longer lenses start to get more expensive, like the wide angle issue. The Pentax-M series has some good options at 100/2.8, 120/2.8, 135/3.5, 150/3.5 and 200/4. A lot of zooms cover 70-200 or so pretty well, even some f2.8 at reasonable prices.

Last edited by Just1MoreDave; 03-19-2013 at 12:32 PM.
03-19-2013, 01:00 PM   #21
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QuoteOriginally posted by alexmann Quote
OK so downloaded the program and analysed my past shots
It's amazing when you start looking into this, it's often not the lens or lenses you thought it would be, that's why I suggested you doing this exercise in the first place.

Now for the fun bit, lens buying.
03-19-2013, 02:06 PM   #22
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The ExposurePlot idea was a great one - Thanks! :-)

I've now got a bit more to grips with it, and looked at just stuff I shot with my Fujifilm bridge cameras (there's a filter in the program so you can do that, which is nice). This excludes pics taken with my wife's point n click canon, my iphone etc. Shows a slightly different picture;



This makes things look a bit clearer on the prime end! So I'm thinking a wide angle, a 35 and a 55...would that make sense?

You're right though, I'd have struggled making this analysis without the program!

03-20-2013, 04:07 AM   #23
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QuoteOriginally posted by alexmann Quote
but the real question here is utility - which lenses do people find they use most?
I have a few primes: The ones that are always in my bag (I have a shelf as well) are the FA28, FA35, FA50 & D-FA100... I could survive without the 28 and 50... The FA35 is my most used lens by far...
03-20-2013, 04:28 AM   #24
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I've bought a few on ebay (some with old film cameras) based on this and the lens reviews...I'll keep everyone posted on how they turn out. Even knowing the size and narrowing it down by lenses from the reviews there's still a huge variety! I've gone for a real mix and am excited to see how they turn out. Any that don't work for me I'll resell and chalk up to experience, then when I've found my "niches" I'll upgrade as money allows (if needed - some of the lenses I've acquired score very highly based on others).

Anyway, thanks for all the help everyone - I was amazed at how quickly people responded and how useful the information was - you're all very inspirational!
03-20-2013, 05:01 AM   #25
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QuoteOriginally posted by alexmann Quote
The ExposurePlot idea was a great one - Thanks! :-)

I've now got a bit more to grips with it, and looked at just stuff I shot with my Fujifilm bridge cameras (there's a filter in the program so you can do that, which is nice). This excludes pics taken with my wife's point n click canon, my iphone etc. Shows a slightly different picture;



This makes things look a bit clearer on the prime end! So I'm thinking a wide angle, a 35 and a 55...would that make sense?

You're right though, I'd have struggled making this analysis without the program!
You are welcome. It looks like you have some very clean clusters to consider. The DA35/2.4 is a gem and priced right. If you want AF and a 50mm the new 50/1.8 isn't too expensive but I've seen some F50/1.7s on the market lately that might be better. Anything in the 20-24 range is going to be either harder to find or more expensive. Good hunting.
03-20-2013, 07:02 AM   #26
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QuoteOriginally posted by alexmann Quote
This makes things look a bit clearer on the prime end! So I'm thinking a wide angle, a 35 and a 55...would that make sense
Maybe other's can clear this up for me, as perhaps I am misinterpreting the ExposurePlot, but is alexmann's data not still expressed in 35mm equiv. ? Thus the 24-28mm, 35mm, and 50-55mm clusters would correspond to 15-18mm, 21-24mm, and roughly 35mm on the 1.54x APS-C sensor ? Maybe I am wrong.
03-20-2013, 11:34 AM   #27
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QuoteOriginally posted by alexmann Quote
I've gone for a real mix and am excited to see how they turn out. Any that don't work for me I'll resell and chalk up to experience, then when I've found my "niches" I'll upgrade as money allows
This sounds like a fairly good idea as long as you can separate your judgement of specific lenses in terms of both image quality AND focal length...

You may have a 28 or 50 with awful image quality but don't discount the usefullness of the focal length...

Experiment - Play - Enjoy!!
03-20-2013, 12:05 PM   #28
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Your ExposurePlot data is almost similar to the one I had, when i was using nikon d3000+18-55 kit & 55-200.
So, when I upgraded to K-5II, I end up buying 15, 35 macro & 77...all limiteds (look at the focal lengths, 15, 15x2 & 15x4) and I only shoot with primes.
03-20-2013, 12:30 PM   #29
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QuoteOriginally posted by Santoku Quote
Maybe other's can clear this up for me, as perhaps I am misinterpreting the ExposurePlot, but is alexmann's data not still expressed in 35mm equiv. ? Thus the 24-28mm, 35mm, and 50-55mm clusters would correspond to 15-18mm, 21-24mm, and roughly 35mm on the 1.54x APS-C sensor ? Maybe I am wrong.
Focal length is focal length. Crop factor is different. THe DA35mm is a 35mm lens but on the K-5 it has the field of view like you would get with a ~55mm on a full frame camera. The lens is still a 35mm lens.
03-20-2013, 01:03 PM   #30
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ExposurePlot with Pentax dSLR

QuoteOriginally posted by Docrwm Quote
I'd take a look at the photographs that you have taken with your current zooms lenses and use something like ExposurePlot to look at the focal lengths via the Exif data. An analysis of your photos can lead you to seeing clusters within your current focal lengths that would guide you toward what Prime lenses would best suit your actual photography.
Exposureplot looks like a slick tool. I downloaded it and set it free to scan all my photographic folders. Only it returns "None of the jpeg files contained EXIF info." ... I shoot RAW+ so there are lots of jpg files, and I know the EXIF data is there. I also tried it on folders with just Pentax K-r jpegs, and tried it on folders with just jpg photos from an Olympus P&S that are also known to have EXIF data.

I hate to bug folks for tech support, but any ideas what I am doing wrong?
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