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01-08-2016, 02:33 PM   #1
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Input focal length with a manual not prime

New guy here, mainly only used Canon DSLR's never had a mirrorless camera. Thought I would try the Q7 for some birding with its nice 4.6 crop factor. My first question is about using manual canon FD lens on the Q7.

I was unsure what to input when I pair my new Q7 with a couple of my Canon SLR zoom lens? When prompted with "Input focal length" and I'm using something like a 60mm-300mm do I put in 300mm?

Looking through the user manual it says "When using a zoom lens, select the actual focal length which the zoom is set to." Does that mean i have to re-input the focal length if I zoom in or out at all?

Sorry this sounds like a beginner question, and when I searched I found some threads but they were usually asking why the input focal length screen was coming up with there standard pentax lens. I hope this hasn't been asked several times.

Thanks
-Ash

01-08-2016, 02:45 PM   #2
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Hi Amcsorley. Welcome aboard the forum. That is a great 1st question which unfortunately I cannot answer for you, but be patient and 1 or 2 ( or 10 !! ) of the members will be able to.
01-08-2016, 02:50 PM   #3
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The camera wants to know the focal length so shake reduction works properly: it jiggles the sensor to compensate for motion during the exposure, and how it does so depends on the focal length of the lens. So the more accurate your input is the better SR will work.
01-08-2016, 02:53 PM   #4
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Conventional wisdom has it that you should set the SR to the shortest focal length. That will provide less SR compensation at the long end of the lens, but that beats overcompensation, possibly resulting in blurry images.

01-08-2016, 02:59 PM   #5
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You have a number of choices, and it all boils down to how efficiently you want the shake reduction system to work.

1. Select the shortest focal length

no over-compensation, but possibly sub-optimal stabilization at the tele end

2. Select the focal length you most frequently use
3. Select a focal length in the middle


convenient but you risk sub-optimal or over-compensation

4. Change the focal length via the menu after zooming

the most time-consuming, but you're guaranteed optimal stabilization

So it's really up to you. Option #1 lets you set it and forget it at the expense of optimal stabilization. Options #2 or #3 are good if you know where you typically use the lens. Option #4 is the most rewarding but also the most demanding.

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01-08-2016, 03:00 PM   #6
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Thanks guys, for the 60mm-300mm I was putting in 300mm, but I see your point luftfluss

Thanks!

---------- Post added 01-08-16 at 03:01 PM ----------

Thanks for the info Adam!

I didn't even think about the SR all good input.
01-08-2016, 03:14 PM   #7
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FWIW, I always just turn the SR off when using zooms on my DSLRs. Unless I absolutely need to shoot slower than the focal length, the need for SR is minimal enough to not worry about it.
01-08-2016, 03:33 PM   #8
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See what I mean about the forum Amescorley. 55 minutes to get your answers. I have never used a Q7 or non-Pentax lenses, but somebody here has. Looking forward to seeing some of your photographs.

01-08-2016, 03:39 PM   #9
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QuoteOriginally posted by Sagitta Quote
FWIW, I always just turn the SR off when using zooms on my DSLRs. Unless I absolutely need to shoot slower than the focal length, the need for SR is minimal enough to not worry about it.
But using a FD lens on a Q it will be using the electronic shutter. So it is 1/40s no matter what. Using it on anything other than a tripod will probably lead to jello-effect anyway.
01-08-2016, 07:45 PM   #10
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QuoteOriginally posted by Adam Quote
You have a number of choices, and it all boils down to how efficiently you want the shake reduction system to work.

1. Select the shortest focal length

no over-compensation, but possibly sub-optimal stabilization at the tele end

2. Select the focal length you most frequently use
3. Select a focal length in the middle


convenient but you risk sub-optimal or over-compensation

4. Change the focal length via the menu after zooming

the most time-consuming, but you're guaranteed optimal stabilization

So it's really up to you. Option #1 lets you set it and forget it at the expense of optimal stabilization. Options #2 or #3 are good if you know where you typically use the lens. Option #4 is the most rewarding but also the most demanding.
I have wondered if using a TC would change the focal length setting on the camera. Say, a 100mm lens with a 2x tele converter. Go with 100mm or 200mm or split the difference at 150mm?
01-08-2016, 10:05 PM   #11
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A 100mm lens with a 2x on the back has a focal length of 200mm. Use that. The camera has a scale built into its firmware that calculates the magnification of the motion blur using the internal movement detector and the speed of the equivalent motion of the image at the sensor resulting from the focal length.
01-08-2016, 11:07 PM   #12
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QuoteOriginally posted by boriscleto Quote
But using a FD lens on a Q it will be using the electronic shutter. So it is 1/40s no matter what. Using it on anything other than a tripod will probably lead to jello-effect anyway.
Boriscleto would the Q7 always use 1/40s and the electronic shutter when using any manual lens? I was also curious if any non Pentax q mount lens even have the ability to do auto focus or adjust the apature via the camera?

Thanks
-Ash
01-09-2016, 08:35 AM   #13
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QuoteOriginally posted by Amcsorley Quote
Boriscleto would the Q7 always use 1/40s and the electronic shutter when using any manual lens? I was also curious if any non Pentax q mount lens even have the ability to do auto focus or adjust the apature via the camera?

Thanks
-Ash
The Pentax Adapter Q for K-mount lenses has a leaf shutter, so the camera is not limited to the electronic shutter. But it is still limited to manual focus and aperture.

Pentax Adapter Q for K-mount Lenses 39977 B&H Photo Video!

Only the 01, 02, 06 and 08 have auto focus and aperture.
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