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10-09-2011, 12:57 PM   #16
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QuoteOriginally posted by G_Money Quote
In your opinion does optical cropping become less desirable if the image is destined for print? If your printer required a minimum of say 200ppi then a K-5's resolution of 4928 pixels (long edge) would give a print of 24.6 inches. Without resorting to image resampling, a 1.4X crop would only allow a print of 17.6 inches. To get back to the 24.6 inch print, do you think resampling would be better or worse than optical cropping using the full resolution?
I don't think there is a clear answer to the question. There are a whole series of trade offs many of which are not under your control that I think
drive the decision.

The best way to screw up a photo is to get it out of focus. the object of your affection needs to be both big enough and bright enough in the viewfinder for you to get the focus 'right on'. This is vastly more difficult with the A*600 than with thte A*400. While bigger and brighter are reciprocial, If the object isn't big enough to see, brighter doesn't matter. This consideration tilts to optical cropping unless the lighting is really difficult.

Another way to screw up a photo is to get the exposure really bad. While the instant review is helpful, around here the dominant 'background' is
a very dark green douglas fir tree. If this 'background' dominates the scene it will burn out the foreground target. While this can be mitigated some using single point exposure option, the point is that extraneous lighting conditions can cause a lot of grief which can be mitigated with optical cropping.

Conversely, If you are trying to take a picture of a moving target...... leaves fluttering, animals moving, birds that may fly away, while you are trying to bolt your camera to a block of concrete so it won't vibrate, take the picture and fix it in photoshop.

Composition is much easier in photoshop. You can drag the crop lines around to your satisfaction. Something you can't change if you do 'incamera' cropping. Also the converter effectively magnifies any optical imperfections. If use one, edge fall off can be expected,
but can be mitigated by 'stopping down'. Strong lighting conditions can be expected to greatly improve optical cropping results.

I should mention that I exclusivelyl use RAW images for what I've done here. The JPG compression of necessity tosses some detail, and since large hard drives and large memory cards are cheap, There is no excuse for stuffing 10 lbs of stuff in a 5 pound bag as the JPG algorithm does
until you have decided on what the final composition should be.

I can go no further than say that the optical converter is not a free lunch. the cropping that it accomlishes optically leaves less that you can do
digitally. They are reciprocials, but like trading f stops for shutter speed, there are a whole hose of external reasons for pushing the envelope one way or the other.

What I actually set out in this thread to do was explore whether owning both a A*400 f2.8 and an A*600 f5.6 made any sense at all.
Superficailly it would seem that you can slap a 1.4x converter on the A*400, or the 1.7x adapter,and have and effective focal length
similar to the 600, and perhaps have some speed to spare. Were that always the case, owning both would be pointless.

It turns out not to be the case. While the A*400 f2/8 is probably the most impressive optic that I have ever had my hands on, and even though
I've owned its baby brother, the A*300 f2/8 for a decade or more, the 400 continues to impress me with its abilities--and it's not just the focal length I've owned a couple different 'slow' 400's and have disgarded them. I've got for example a SIGMA 400 f5.6 that is auto focus, but I haven't put it on the camera in years because the buzz isn't there.

But as unique as the A*400 is, It isn't a 600, and when the 600 gets in its element--- (enough light that the f5.6 limitation doesn't cripple it), the best 400 in the world won't keep up.

Not a solid answer here, but I would look real hard at the lighting when setting up for the photo. Reallly strong lighting and nothing moving (neither the target nor the camera) are the best for optical cropping, but if you have weak light and a strong gusting crosswind....

10-10-2011, 06:59 PM   #17
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QuoteOriginally posted by audiobomber Quote
Interesting tests rvannatta. I think not locking the shutter up is more realistic of real world use.

I have a new-to-me A*300mm f/4, with a Kenko 1.4 Teleplus and Pentax 2X-S. I haven't had any of this gear long enough to draw solid conclusions, so I'll be watching this thread with interest. I've only had one real outing, shooting small birds with the bare A*300. I was very pleased with the results, but had to do major cropping in post. With a TC on an f/4 lens, I'm going to need lots of light or very high ISO's.

A simple rule (probably too simple) occurred to me from your testing and my limited experience. For computer viewing and internet posting, a digital crop will usually look better. For prints you would benefit from more pixels, so the TC should beat cropping.

Not locking the mirror up may well be more 'real world', but doing so made a very significant difference in results. Once I figured out how,
its not hard to do or use. It's in the same menu where you activate the self timer and/or the remote wireless. The last item on the row of options is "wirelless + Mirrorup". It's pretty slick actually. You then have to push the remote wireless twice for each photo. First time lifts the mirror, and the second time takes the photo.

On my first run throughs without the mirror locking, the vibration was obvious in the results with the TC despite using an expensive and highclass tripod. This simply went away with the Mirror lockup.

I knew it was an issue with the 600 from observations I had made some years ago when I attempted to use my A*600 with a very cheap
lowend tripod. You hit the release and you could actually see the lense bobbing up and down in response to the 'release'.
10-10-2011, 07:27 PM   #18
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This is an interesting thread!

I own a 600/5.6 lens and regularly use it without a TC. I'm happy with it's performance. Sometimes I wish I owned a 600/4 for better light gathering, but I think the K-5 will work. As you have alluded to somewhat - putting aside proper support systems, etc. - it's the technique(s) used with your equipment & subject proximity that matters.

I regularly photograph very small subjects with reasonable success and no mirror lockup, just solid long lens technique. Factor in a K10D that is limited bu it's sensor + AF capabilities on frequently moving targets and you have a great recipe for frustration on occasion!

Regards,
Marc
10-10-2011, 11:48 PM   #19
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QuoteOriginally posted by Marc Langille Quote
This is an interesting thread!

I own a 600/5.6 lens and regularly use it without a TC. I'm happy with it's performance. Sometimes I wish I owned a 600/4 for better light gathering, but I think the K-5 will work. As you have alluded to somewhat - putting aside proper support systems, etc. - it's the technique(s) used with your equipment & subject proximity that matters.

I regularly photograph very small subjects with reasonable success and no mirror lockup, just solid long lens technique. Factor in a K10D that is limited bu it's sensor + AF capabilities on frequently moving targets and you have a great recipe for frustration on occasion!

Regards,
Marc
Can't disagree here. I just got my 600 repaired. It had had a problem since I had purchased it, and it had taken me some years actually to find
a repairman that I trusted enough to leave it off. While it was still in the shop and without knowing whether it was repairable or not (it needed to screws it turned out) the opportunity to get the 400 f/2.8 came up, and since those don't show up very often, I grabbed that, and then the 600
got its internal screws, and works like a clock.

Since, I had a pocket full of converters, my inspiration for the thread was to convince myself whether or not I should peddle one of the lenses
or the converters, or to at least define when each was best used.

after 3 different shoots and analyizing a 150 or so pictures in photoshop, and publiclly arguing with myself for a week, I think I have figured out what likely everyone else on the planet already knew.

Both of these lenses are amazing performers, but slapping a TC on a 400 doesn't make a 600. It's a 400 with a TC. Duh!. With modest enlargement, however, you likely can't tell the 400+TC photo from the 600, but when you get to Photoshop, and start heading for the
ceiling of how much you can elarge the photo you find the difference real quick. A TC is NOT a free lunch upgrade of a short(er) lens to a long(er) lens.

The 600 works well with A TC also. If you manage the shake and vibration you can get there---even with the TC's stacked. but you have to keep remembering that mostly what you accomplish with the TC is to make the image larger in the viewfinder, but the ultimate maximum size you
can get the 'subset of the image you were after won't be that much different.

One thing I have noticed clearly though is the impact of a TC on the depth of field.---- seemingly none. As you well know the DOF on the 600 is pretty skinny unless you are a very long ways away. The 400 has 'more' depth of field, but slapping a TC on the 400 doesn't seem to change this (more), so even though the images are superfically the samesize, at least my perception is that the optical crop of the TC doesn't alter
the longer DOF of the 400. I always wonder if I am imagining these things, but that is my perception.

I also agree with you that the K5 makes using these monsters much easier. The enhanced ability of the K5 to use elevated ISO's is a major plus.

-----
On a related issue: what do you do about the 'off balance' issue of the 600. I've see commercial adapter plates to allow one to balance such a lens, but since I know how to run a machine shop, I've actuallyl been onsidering making my own.... It's on the TO DO list.

10-11-2011, 06:39 AM   #20
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QuoteOriginally posted by rvannatta Quote
Not locking the mirror up may well be more 'real world', but doing so made a very significant difference in results. Once I figured out how,
its not hard to do or use. It's in the same menu where you activate the self timer and/or the remote wireless. The last item on the row of options is "wirelless + Mirrorup". .
I don't see that option with my K20D or K-x.
10-11-2011, 07:26 AM   #21
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QuoteOriginally posted by audiobomber Quote
I don't see that option with my K20D or K-x.
Nor do I see it on my K10D, and I don't have a K7 handy to check, but the K5 has a MUP option-- on the 'release mode' menu which also contains
a laundry list of other release options: bracket exposing, self timer, wireless remote, continious exposing (flails away as long as you hold the button down). MUP actually opens a sub menu of dtwo MUP options. --- one is for manual release, and the other is for wireless release. (turns the blinking red light on) I'm not sure of the value of the MUP if you are going to use your fat thumb on the shutter button to release the shutter,
but I suppose this option also works with 'wired remote' releases as well as the wireless.

The big problem with the wireless remote is keeping it out of the washing machine and being able to find it.
10-11-2011, 03:02 PM   #22
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QuoteOriginally posted by rvannatta Quote

I also agree with you that the K5 makes using these monsters much easier. The enhanced ability of the K5 to use elevated ISO's is a major plus.

-----
On a related issue: what do you do about the 'off balance' issue of the 600. I've see commercial adapter plates to allow one to balance such a lens, but since I know how to run a machine shop, I've actuallyl been onsidering making my own.... It's on the TO DO list.
I should clarify and my apologies for the confusion: mine is a slightly different beast - the FA* 250-600/5.6. It's perfectly balanced on a Wimberley WH-200 gimbal with their P-50 plate extended beyond the rear of the tripod collar foot. No setup required 1st time or anytime thereafter: just clamp the plate flush with the rear of the platform and you are set!


Cheers,
Marc
10-11-2011, 03:15 PM   #23
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MLU - unless I misunderstood what you're looking for?

QuoteOriginally posted by audiobomber Quote
I don't see that option with my K20D or K-x.
QuoteOriginally posted by rvannatta Quote
Nor do I see it on my K10D, and I don't have a K7 handy to check, but the K5 has a MUP option-- on the 'release mode' menu which also contains
a laundry list of other release options: bracket exposing, self timer, wireless remote, continious exposing (flails away as long as you hold the button down). MUP actually opens a sub menu of dtwo MUP options. --- one is for manual release, and the other is for wireless release. (turns the blinking red light on) I'm not sure of the value of the MUP if you are going to use your fat thumb on the shutter button to release the shutter,
but I suppose this option also works with 'wired remote' releases as well as the wireless.

The big problem with the wireless remote is keeping it out of the washing machine and being able to find it.
Self Timer Shooting on K10D - firmware 1.3:

FN button --> up arrow--> Drive Mode --> right arrow --> then select:

Single Frame Shooting
Continuous Frame Shooting
Self Timer (2 sec.)
Self Timer (12 sec.)
Remote Control Unit
Remote Cont. (3s delay)


Self Timer Shooting on K20D is nearly the same menu.


Good to go!

Cheers,
Marc

10-11-2011, 09:03 PM   #24
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QuoteOriginally posted by Marc Langille Quote
I should clarify and my apologies for the confusion: mine is a slightly different beast - the FA* 250-600/5.6. It's perfectly balanced on a Wimberley WH-200 gimbal with their P-50 plate extended beyond the rear of the tripod collar foot. No setup required 1st time or anytime thereafter: just clamp the plate flush with the rear of the platform and you are set!


Cheers,
Marc
that is a somewhat different animal. the A*600 f/5.6 is about 6 inches out of balance which doesn't help anything at all. My present thinking is that I will
machine an offset plate. Having a reasonable balance should make setting the pitch (elevation) a bit easier. Fortunately the A*400 is well balanced which is a good thing since it is so incredibly heavy.
10-12-2011, 04:57 AM   #25
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QuoteOriginally posted by Marc Langille Quote
[B][I]Self Timer Shooting on K10D - firmware 1.3:

FN button --> up arrow--> Drive Mode --> right arrow --> then select:

Single Frame Shooting
Continuous Frame Shooting
Self Timer (2 sec.)
Self Timer (12 sec.)
Remote Control Unit
Remote Cont. (3s delay)
Yes, I know about mirror lockup in timed delay modes, but who wants to wait 2-3 seconds after pressing the shutter for shooting wildlife? Rvannatta is saying the K-5 can lock the mirror up and allow instant shutter release with a remote or cord. My K20D and K-x don't have this feature.
10-12-2011, 08:34 AM   #26
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QuoteOriginally posted by audiobomber Quote
Yes, I know about mirror lockup in timed delay modes, but who wants to wait 2-3 seconds after pressing the shutter for shooting wildlife? Rvannatta is saying the K-5 can lock the mirror up and allow instant shutter release with a remote or cord. My K20D and K-x don't have this feature.
Neither would I = thought it was a bit odd. That's why the subject line in my post asked if I misunderstood. Thanks for the explanation of what you were trying to sort out.

Regards,
Marc
10-12-2011, 08:35 AM   #27
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QuoteOriginally posted by rvannatta Quote
that is a somewhat different animal. the A*600 f/5.6 is about 6 inches out of balance which doesn't help anything at all. My present thinking is that I will
machine an offset plate. Having a reasonable balance should make setting the pitch (elevation) a bit easier. Fortunately the A*400 is well balanced which is a good thing since it is so incredibly heavy.
The 250-600/5.6 is 'butt heavy" when not using the gimbal setup I have described. It's a definite problem if you try to use a monopod setup.

Regards,
Marc
10-12-2011, 10:48 AM   #28
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QuoteOriginally posted by rvannatta Quote
that is a somewhat different animal. the A*600 f/5.6 is about 6 inches out of balance which doesn't help anything at all. My present thinking is that I will
machine an offset plate. Having a reasonable balance should make setting the pitch (elevation) a bit easier.
The A*600's tripod mount is small and I agree that it is unbalanced.

Get a very long lens plate and put a couple layers of that self-adhesive insulation you use for windows/doorways at the very front end (to be precise, the anterior) of the plate. This will allow bottom of the front of the A*600 to rest on the front of the lens plate and let you better balance the A*600 on a tripod. I was able to buy a generic but high quality long lens plate on flea-bay for about $40 shipped. This is the advice I gave to the person who bought my A*600 from me earlier this year.

Your other option is to get a Really Right Stuff long lens support but that costs 6-7x more money.
10-12-2011, 01:55 PM   #29
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QuoteOriginally posted by Marc Langille Quote
Neither would I = thought it was a bit odd. That's why the subject line in my post asked if I misunderstood. Thanks for the explanation of what you were trying to sort out.

Regards,
Marc
there is no 'fixed time' imposed by the MUP feature of the K-5 with a wireless.
You simple have to push the release button twice. the minimum delay is a function of how quickly you can push the buttom twice.
10-12-2011, 02:09 PM   #30
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QuoteOriginally posted by tranq78 Quote
The A*600's tripod mount is small and I agree that it is unbalanced.

Get a very long lens plate and put a couple layers of that self-adhesive insulation you use for windows/doorways at the very front end (to be precise, the anterior) of the plate. This will allow bottom of the front of the A*600 to rest on the front of the lens plate and let you better balance the A*600 on a tripod. I was able to buy a generic but high quality long lens plate on flea-bay for about $40 shipped. This is the advice I gave to the person who bought my A*600 from me earlier this year.

Your other option is to get a Really Right Stuff long lens support but that costs 6-7x more money.
will a full machine shop at my disposal, I need only wake up with determination.
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