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Old Mar 11, 2018, 5:37 PM   #21
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Mtngal,

Ira,

It was a nice warm weekend her in Milton, but . . . I ended up spending most of my weekend cleaning up around the house.

I have a Pentax-A 70-210mm f/4 lens. I did try it out, but it has been so long since I had it out that I can't remember much about it.

Have you gotten the split prism focus screen yet?

I'd image that would go a long way to helping use the longer lenses?

Take care!
The screen arrived and works perfectly. It is an interesting double split diagonal with a microprism circle surrounding the split image centre. It seems to be very accurate with lenses of 50mm or longer. The 28mm is more difficult but stop it down a little and use zone focusing since it has far greater depth of field.
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Current equipment
Pentax *istDS, K10D, K3:
FA 50 f1.4, FA 28-70mm f4, FA 28-80mm f3.5-5.6, FA 80-320mm f4.5-5.6, F 50mm f1.7, Tamron SP 70-200mm f2.8 Di, DA 10-17 f3.5-4.5, DA 14 f2.8, DA 16-45mm f4, DA 18-55mm f3.5-5.6, DA 18-135mm f3.5-5.6 WR, AF-540FGZ

Olympus E-P5, OM-D E-M1: 9mm to 150mm lenses

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Old Mar 12, 2018, 2:35 PM   #22
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Ira,

That sounds great! As for the double split, do you mean one on each side of the center AF point? So the center of the focus screen is flat?

As for the microprism circle . . . that is like the old focus screens from the film days.

I can't remember which camera I had but it only had that, no split prism.

I might be shooting tonight. My daughter wants to go out to get shots for her photography course she is taking at school.

She is using a Pentax ist DS with kit lens. I told her I'm going to make her try the Pentax-A 50mm f/2 I gave her if we go out tonight.

I'm going to drag out my Pentax ist DS with my Sigma 18-200mm superzoom. But also, if we go out, I'm taking a Gossen Lunasix F to show my daughter how to use a handheld light meter.

We'll see. She was working today, so might be tired. And its snowing a bit right now.
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NOTE: I'm trying to capture the picture in my head! Not the one my camera sees!

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Old Mar 13, 2018, 2:40 PM   #23
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Iíll try taking a picture of it with my phone.
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Ira
Riverview, NB, Canada
http://aicphotography.blogspot.com/
_______________________________
Current equipment
Pentax *istDS, K10D, K3:
FA 50 f1.4, FA 28-70mm f4, FA 28-80mm f3.5-5.6, FA 80-320mm f4.5-5.6, F 50mm f1.7, Tamron SP 70-200mm f2.8 Di, DA 10-17 f3.5-4.5, DA 14 f2.8, DA 16-45mm f4, DA 18-55mm f3.5-5.6, DA 18-135mm f3.5-5.6 WR, AF-540FGZ

Olympus E-P5, OM-D E-M1: 9mm to 150mm lenses

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Old Mar 17, 2018, 8:07 AM   #24
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Well, I had my Pentax ist DS out with the 18mm at the wide end of my superzoom at f/5.6 to try focus zone shooting.

Viewed at reasonable size / distance it looks ok.

But pixel peeping, nothing seemed truly in focus as there was very little at 10'. LOL.

I want to take another stab at this.

Two tests are . . . stopping down a bit more. And swapping the Sigma superzoom for my daughter's Pentax 18-55 kit lens. I think the thing with the kit lens is that it doesn't have a marking for 10ft. I'd have to take a measuring tape with me (My judgement of distance is bad) to give this a good go. If it works, I could mark 10' on the lens myself with a silver permanent marker or something.
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NOTE: I'm trying to capture the picture in my head! Not the one my camera sees!

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Old Mar 17, 2018, 5:10 PM   #25
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Thanks for the further discussion. I did pull out the 24 F2.8.8 and played with it a bit. I seemed to have less trouble focusing it with the K1. I used live view with its focus peaking feature. My photos were completely uninteresting, someone on an RV board asked how to operate something, so that was a great excuse.

I didn’t remember that that old lens was as close focusing as it is. It turned out to be very useful for what I was trying to show.

I need to use it more, I kept forgetting about metering and where the green button was. But it was fun, and have I ever gotten lazy about shooting.
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Old Mar 18, 2018, 6:21 AM   #26
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Quote:
Originally Posted by mtngal View Post
Thanks for the further discussion. I did pull out the 24 F2.8.8 and played with it a bit. I seemed to have less trouble focusing it with the K1. I used live view with its focus peaking feature. My photos were completely uninteresting, someone on an RV board asked how to operate something, so that was a great excuse.

I didn’t remember that that old lens was as close focusing as it is. It turned out to be very useful for what I was trying to show.

I need to use it more, I kept forgetting about metering and where the green button was. But it was fun, and have I ever gotten lazy about shooting.
+1

I had fun turning everything off and running the camera in as manual a mode as possible.

Manual focus. Manual exposure. I even remembered to bring my handheld light meter with me and used that to pick exposure settings.

LOL.

I did that a little in the film days. And a little when I first got my K100d. But I quickly got used to autofocus and using either Program or Aperture Priority myself.

But I just got this itch to just try to slow down a bit and take my time and start again.

LOL.

I've been contemplating a 24mm f/2.8. Even though I only have APS-C. But 24mm works out to be 35mm. I have a 28-75mm for my full frame Nikon. And I was really astonished how often while shooting my pictures ended up being . . . 35mm focal length. I seem to like that focal length a lot apparently. LOL. So, I've been wondering if that should have been a focal length I got for APS-C.
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NOTE: I'm trying to capture the picture in my head! Not the one my camera sees!

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Last edited by tacticdesigns; Mar 18, 2018 at 6:24 AM.
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Old Mar 18, 2018, 6:30 AM   #27
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Ok. I got another idea for an experiment.

I don't have a full frame (or adapter) to get my 28mm onto a full frame.

I tried shooting zone focusing on my APS-C camera at 18mm on a superzoom.

But I'm wondering if I can get a sense of how the 28mm on full frame compares to 18mm on APS-C.

So I'm thinking of this experiment.

I take 2 pictures with my APS-C camera.

Picture 1 = Sigma 18-200 superzoom set to 18mm, f/5.6, focused to 10 feet.

Picture 2 = Cosmicar 28mm set to 28mm, f/8, focused to 10 feet.

But both pictures standing in the same place, pointed in the same direction.

Then I take Picture 2 and shrink it down so it covers the same part of the image in Picture 1. I might cut Picture 2 in half and only take the right side for this experiment.

That might give me a little hint at how the 28mm at f/8 might look on a full frame compared to 18mm on my APS-C?

I think I'll do that test next week at lunch some time.
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Old Mar 20, 2018, 12:02 PM   #28
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Ok.

So I had a bit of time at lunch today, so I grabbed my Pentax ist DS, my Sigma 18-200mm f/3.5-5.6 superzoom and my Cosmicar 28mm f/2.8 prime.

I shot the Sigma at ISO 200, f/5.6, 1/1000 sec at 10 feet. The settings I figured out for Zone Focusing with a 28mm eq. on the cropped sensor.

And then I shot the Cosmicar 28mm f/2.8 at ISO 200, f/8, 1/500 sec at 10 feet. The settings for zone focusing on full frame.

I then shrunk down the 28mm shot to fit over the same area on the 18mm shot and masked out part of the overlaid image to compare detail between the 2 shots.

Looking at the bark of the tree on the left, I can see the 28mm (lighter image) seems to have more detail.

But it is hard to see for certain in this image. Maybe the 6MP sensor just can't capture the different?

I'm thinking I need to repeat this test on my Nikon cameras. I'll use the 18mm on one of my kit or superzoom lenses on my Nikon D5100 and the 28mm of my Tamron 28-75mm f/2.8 on my full frame and then merge the images together.

But from this little test, I looks like the 28mm will be more detailedl
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NOTE: I'm trying to capture the picture in my head! Not the one my camera sees!

Personal Flickr Favs: http://www.flickr.com/photos/tacticd...7631300869284/
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Old Mar 20, 2018, 7:05 PM   #29
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It does look that way, though the fact you are dealing with a zoom vs. a prime will make a difference. Also, the lighter, 28mm has less clipping in the darks which could potentially show more detail, or at least that's what it looks like to me based on the post above. And I know what you mean - as much as I loved that 6 MP sensor, when I tried to shoot with it (K100) last summer, I was surprised at just how limiting it seemed to me now, and just how much detail I can get out of my current cameras.

I think your idea of doing the same thing with the 2 Nikons would give you a better feel for the differences between the two (APS-C vs. FF). You'll still be battling the problem of using two different lenses with different characteristics though. What you are trying to do is really hard, there's just so many variables involved!
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Old Mar 21, 2018, 11:41 AM   #30
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Yeah. It is a weird test.

I guess . . . the ultimate thing I'm trying to figure out is whether I could run around setting my camera up with zone focusing and be happy with the output.

I have the 28mm lens, but no full frame camera to run it on.

Trying to run through the depth of field calculator, trying to get the 28mm to work on the cropped seemed like a deal breaker so I was trying to see if using the 18mm at the wide end of my superzoom might give me a hint on whether this was at all doable . . . even if I would eventually have to get a full frame.

But the superzoom results were less than what I had hoped to see.

So that got me to thinking . . . is it the lens or because I am on crop.

So to show the difference between the superzoom and the prime, I devised the above test.

And partly it looks like the prime I would be more happy with. But probably only on a full frame body.

But . . . is part of what I am seeing because I am taking the picture taken with the 28mm prime and shrinking it down to fit into the other shot? So is the increase in detail caused by that shrinking down? And conversely . . . is the cropped sensor capture seem less than what I had hoped for because I have to blow it up to view it more so than I would a full frame sensor capture? LOL.

So, this weekend, I think I'll break down and try shooting zone focus on my Nikon full frame with the 28mm (f/8 @ 10 ft) at the wide end of my 28-75 and then compare that to shooting my Nikon cropped sensor camera at 18mm (f/5.6 @ 10 ft) at the wide end of my 18-55.

My cropped sensor Nikon is 16MP, so I might shoot JPG and shoot both at 16MP to even things out a bit.
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NOTE: I'm trying to capture the picture in my head! Not the one my camera sees!

Personal Flickr Favs: http://www.flickr.com/photos/tacticd...7631300869284/
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