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Fun with the 645D

tsjanik

Well-known member
Hi,

I am very curious about the 645D. What is the fastest flash sync I can get using wireless. I know the published speed is 1/125, but also it's mentioned that high sync speed can be achieved with wireless. Any insight would be appreciated.
I'm not sure about wireless, but here's a shot I took after I read your post with the 135mm LS at 1/500 s using a 30-year-old 280T.

Thanks for the comment Dave
Tom
 

D&A

Well-known member
Tom Wrote--->"I'm not sure about wireless, but here's a shot I took after I read your post with the 135mm LS at 1/500 s using a 30-year-old 280T."

Tom, your shoot above of the flower (above) supposed my statede (a few posts above), that with one of Pentax's LS lenses, a sync speed of 1/500 is possible. I may be incorrect, but I don't see why it wouldn't be possible with this lens (LS) and wireless strobes? Of course nothing is a substitute foe actually trying such a set-up out.

Dave (D&A)
 

johnnygoesdigital

New member
Thanks for the replies. This is a good start...leaf shutter lenses! I haven't really given the 645D a real consideration until I saw a video of this camera being used in the rain! However, I shoot both landscape and studio and really need to use my Hensel kit with this set-up via wireless. Leaf shutters will get me closer to higher sync, so i'll try that route first. Thank you.
 

tsjanik

Well-known member
..........., but I don't see why it wouldn't be possible with this lens (LS) and wireless strobes? ......Dave (D&A)
I suspect it would work as well. At the very least, a small on-camera could be used to fire slaves.
 

aboudd

New member
Fighting with the weather gods

A week in California (Carmel, Monterey and San Francisco) didn't yield much. Lots of clouds and fog offered mostly flat light. In spite of that, here are a few images I managed to capture.
 
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tsjanik

Well-known member
I like the bridge shots Aboudd. I had the opposite weather problem at Yellowstone - sunny almost every day . Here's an exception. A shot of a photographer in the Hayden Valley and a actual pixel crop (400mm). Humans were the only wildlife to be seen that evening:mad:
Tom
 

benroy

Subscriber Member
Coming over from the Pentax K-5 forum having purchased a 645D. Bought a 55/2.8 A before making the purchase, using it on a Canon 40D. I use the garden on the other side of my fence as my studio. I am really impressed with this lens...haven't seen any raves for it in this forum, however.

Roy Benson
 
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tsjanik

Well-known member
Hi Roy:

I see you took the plunge! In my experience and in the reports I've read, the 55mm is a good lens, sharp in the center and a bit weaker at the edges. For the images you've posted, soft corners are no concern. Many have found the 45-85mm zoom to be better than the 55 or 45mm primes. You pay a price in weight with that lens however. Did you buy the 645D new?

Tom
 

D&A

Well-known member
Hi Roy:

I see you took the plunge! In my experience and in the reports I've read, the 55mm is a good lens, sharp in the center and a bit weaker at the edges. For the images you've posted, soft corners are no concern. Many have found the 45-85mm zoom to be better than the 55 or 45mm primes. You pay a price in weight with that lens however. Did you buy the 645D new?

Tom
+1 to what Tom expressed. The FA 45-85 lens is generally terrific, especially between 45-65mm and beyond 65mm, gets a bit weak in the corners/edges (varies from sample to sample). Unfortunately this zoom like many of the FA lenses, requires both finding a well calibrated sample as well as adjusting the 645D body's AF fine tune for this lenms. With zooms, the AF fine tune adjustment must be made with the lens at a focal length which has the most impact. On most samples of this lens, its generally between 65 and 85mm.

Dave (D&A)
 

benroy

Subscriber Member
Thanks, Tom and Dave, for your suggestions. I've had the 645D for a day now...handling is fine, but, my, it's a noisy rascal...the mirror bangs up with a crack! Would be a real attention-getter during a wedding ceremony...also was disappointed at how slow the SD card functions...but then I forget it's working on 40 mb.

I have purchased a 45, 55, 75, 120 macro, and a 200/4. All A lenses. Total amount spent: less than $1000, thanks to Atlanta's Wings Camera's offerings on eBay. I've tried the 55 and the 200 on the 645D. 55 is very good...200 echhhhh, so far. Tried the 120 macro on the Canon 40D...very fine lens.

More to come as I get into this a bit more.

Roy Benson
 

D&A

Well-known member
Hi Roy,

I realize the lenses you're using currently are manual focus versions...some of which had the same optical formula as their AF counterparts (and a few that didn't). I mention this since some (not all) of the AF versions (FA lenses) require very strick AF fine tune adjustment on the 645D body, in order to extract good (better) performance. The other thing thats critical is finding samples who's initial factory adjustments are a good match when used with a sensor based camera (like the 645D. regarding this latter point, I was extremely disappointed with the FA AF 200 f4 lens and went on to test more samples. After quite a few samples (all performing mediocre at best), I found one that was exceptionally good, even at f4. THis confirmed what I found in many other FA focal lengths..that indivudal samples can make an astonishing difference. The one lens that was always consistant from sample to sample was the FA 120mm f4 macro. I suspect this is because in the film days when all these lenses were manufactured, tight tolerances was needed for macro lenses (especially in their macro range)..whereas other lenses, just had to be "close" since it was being used with film, which is more forgiving. I've been meaning to post my comprehensive Pentax 645 lens tests with most all FA lenses, but can't quite finish writing it up. Hopefully soon.

Dave (D&A)
 

benroy

Subscriber Member
Looking forward to the results of your comprehensive testing, Dave. All of the lenses I have are "A" lenses, but an interesting anomaly has risen that is apropos of your comments about fine tune adjustments. I have a 200/4A lens that renders tack sharp images when used with an adapter and Canon 40D...when I put the 200 on the 645D, less than 10% of the images are anywhere near sharp...they look sharp in the viewfinder, but when they show up on the computer monitor screen, they are not.
The only other lens that I have used on the 645D is the 55/2.8 and that has been fine.
Conclusions? 200/4 needs fine tuning in the 645D?

Roy Benson
 

D&A

Well-known member
Looking forward to the results of your comprehensive testing, Dave. All of the lenses I have are "A" lenses, but an interesting anomaly has risen that is apropos of your comments about fine tune adjustments. I have a 200/4A lens that renders tack sharp images when used with an adapter and Canon 40D...when I put the 200 on the 645D, less than 10% of the images are anywhere near sharp...they look sharp in the viewfinder, but when they show up on the computer monitor screen, they are not.
The only other lens that I have used on the 645D is the 55/2.8 and that has been fine.
Conclusions? 200/4 needs fine tuning in the 645D?

Roy Benson
I haven't specifically worked with many of the manual focus "A" lenses on the 645D, but I suspect that if you are using the AF confirmation light in theviewfinder to determine correct focus, then of course AF fine tune will alter the point when this light comes one. If this is the case, then AF fine tuning will certainly help. The issue I had wither certain Af lenses is not only having to AF fine tune them, but also certain sample were far better than others...even though each was fine tuned with the 645D AF fine tune system. So its a two fold issue.

BY the way, purchasing fast SDHC cards won't speed up the camera processing the images. reason being is Pentax, in order to save money in production costs and therefore the price point the camera is sold at...put in a slow processor. The limiting fator is therefore the processor, not using average speed cards. So save you money for lenses, not cards.

Dave (D&A)
 

Charles Wood

New member
BY the way, purchasing fast SDHC cards won't speed up the camera processing the images. reason being is Pentax, in order to save money in production costs and therefore the price point the camera is sold at...put in a slow processor. The limiting fator is therefore the processor, not using average speed cards. So save you money for lenses, not cards.

Dave (D&A)
I found with my 645d by only enabling writing to one card and using RAW, the length of time from shutter release to image display is barely one second. The time lengthens of course, with two cards and writing RAW+JPG to each card.

A fast SDHC card does offer the potential benefit of faster read time when downloading images.
 

D&A

Well-known member
I found with my 645d by only enabling writing to one card and using RAW, the length of time from shutter release to image display is barely one second. The time lengthens of course, with two cards and writing RAW+JPG to each card.

A fast SDHC card does offer the potential benefit of faster read time when downloading images.
Hi Charles,

If you are refering to when the image shows up briefly on the LCD sceen for a couple seconds (for a quick look) after pressing the shutter, then I believe this is simply a quick look at the file from (using) the camera's buffer..although maybe a slightly faster card might help a bit.....BUT...if we're refering to the write time the camera takes to actually write the file(s) to the card (so that image also can be viewed indefinitely on the LCD screen, then most everyone has experienced fairly long and slow write times which weren't helped by using expensive fast cards. In this case, a moderately priced regular class 6 card did about as well as the fastest and most expensive cards on the market. I (and others) have tried this actual experiment on a number of occasions with well controlled "timed" tests and it made little to no difference which decent and moderately priced fast card was used. It appears the processor is the limiting factor in its processing speed to process and write images to the card. As sort of compensation, the buffer on the 645D is of decent size, so at least one can fire off a good numer of shots in succession.

Dave (D&A)
 
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Charles Wood

New member
Hi Charles,
I (and others) have tried this actual experiment on a number of occasions with well controlled "timed" tests and it made little to no difference which decent and moderately priced fast card was used. It appears the processor is the limiting factor in its processing speed to process and write images to the card. As sort of compensation, the buffer on the 645D is of decent size, so at least one can fire off a good numer of shots in succession.

Dave (D&A)
I don't disagree with your statement. My personal work around was to set the quick digital preview to five seconds. I found when taking a single frame by the time the preview disappeared, a touch of the image button brought up the written file within a second or so, if I wanted to digitally enlarge the file to check focus, etc.

There are actually two other issues I'm finding more bothersome than the write times. The first is the AF Fine Tune. On my K-5, I have the option of applying the adjustment to One or All lenses. On my 645D there is not a One option. The fine tune can only be applied to All. Do others here find the same with their 645Ds? If so, I am wondering why Pentax made the decision to disallow the One option on the 645D.

Second issue: Optical DOF preview. Again, on my K-5 when I use the Optical Preview position on the On/Off switch ring, I can check depth of field. When I do the same thing on the 645D the shutter trips. What have I missed?

Thanks!
 

Shashin

Well-known member
There are actually two other issues I'm finding more bothersome than the write times. The first is the AF Fine Tune. On my K-5, I have the option of applying the adjustment to One or All lenses. On my 645D there is not a One option. The fine tune can only be applied to All. Do others here find the same with their 645Ds? If so, I am wondering why Pentax made the decision to disallow the One option on the 645D.
That option exists on the 645D. What firmware are you using?

Second issue: Optical DOF preview. Again, on my K-5 when I use the Optical Preview position on the On/Off switch ring, I can check depth of field. When I do the same thing on the 645D the shutter trips. What have I missed?

Thanks!
You have your preview setting on the menu set to digital or electronic or something. Sorry, I don't have my 645d with me right now. But I have my 645D set to stop the aperture down with the on/off switch.
 

Charles Wood

New member
I solved both problems. I was using a manual focus lens when I attempted the calibration. Duhhh!

I thought I had set the digital preview to Off but I had not. Now working OK.

Thanks!
 

D&A

Well-known member
I solved both problems. I was using a manual focus lens when I attempted the calibration. Duhhh!

I thought I had set the digital preview to Off but I had not. Now working OK.

Thanks!
Hi Charles,

Glad problems are solved and thanks for the lively discussions. Yes, with an AF lens, Af fine tune can be applied to one lens or to all. Applying to all makes no sense since each lens on the 645D requires a different Af fine tune setting. Thanks!

Dave (D&A)
 
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