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11-15-2012, 12:10 AM   #31
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QuoteOriginally posted by erwinsie Quote
hi if anyone can compare the official PK to Q adapter vs the ones from ebay, greatly appreciated.
the official is wayyyy too expensive for me
To me, the difference in that 1/1000 and 1/250 flash sync speed with the OEM adapter over the 1/15 on a 3rd party one is worth it.


For macros and birds/animals where you want to use the flash either to light the subject or provide some lift in the shadows, its a day and night difference in fact....

11-15-2012, 12:28 AM   #32
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QuoteOriginally posted by barondla Quote
Not sure what you are refering to?
thanks
barondla
Was referring to this:

QuoteOriginally posted by barondla Quote
Doubt HSS will ever work on the Q. It is designed to overcome the weakness of a focal plane shutter.
When I first read this it was my interpretation that you meant that it doesn't make sense to include because Q uses leaf shutters. The way I see it, features like HSS, Wireless P-TTL, and contrast-control P-TTL (and probably P-TTL wireless commander for built-in flash as well) are essentially features that are implemented in the firmware, and already exist on other Pentax models (some of this is even on the K-01 that has very similar ergonomics & firmware).

In my opinion, a camera that purports to have SLR-like features (and was priced that way on release) shouldn't skimp on this stuff that doesn't even cost Pentax very much to include, and don't add a lot of complexity to the user-experience either.

Due to the diffraction-limited resolution, there's that much more reason to want to shoot with higher shutter speeds & wider apertures with daylight-sync fill flash -- and Pentax has declined to offer HSS which it could have done at little cost.

The hardware feature that I think Pentax skimped out on was lack of a orientation sensor. Why practically every cheap compact digicam has an orientation sensor but Pentax doesn't include one on most of their compacts -- even their best ones -- I don't understand, and it makes me think they're being cheap despite the purported 'premium' market placement and pricing.
11-15-2012, 01:34 AM - 1 Like   #33
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AndrewG Ny, agree with you about wireless P-ttl, contrast control P-ttl, and P-ttl wireless comander. They probaby could work on the Q. It might be possible to enact them with firmware update The K-01 could have these features for sure.

The leaf shutter changes things greatly on the Q vs a focal plane shutter. The focal plane shutter is a "slow" shutter. The one Pentax uses on their DSLR's has a top speed of 1/180 second! Some pro canikons raise this to ~1/250. A focal plane shutter starts at one end and travels to the other, opposite end. The max flash sync speed is the fastest shutter speed where the whole focal plane is open at the same time. To get faster available light ( no flash) shutter speeds ALL focal Plane shutters employ a trick. They form a slit that scans across the focal plane. By covering up part of the opening during exposure, we achieve a faster shutter speed. This trick works fine with continuos light. Flash exposes the trick. Where ever the slit is electronic flash freezes it for all to see. To gain one full step higher shutter speed past the fastest sync speed ( 1/180 to1/360) requires a slit that is half the size of the focal plane opening. With electronic flash this would mean 1/2 of the frame would be exposed.

HSS and other systems extend the duration of the flash by flickering it. This allows higher flash sync speeds. Leaf shutters start in the center of the frame and don't have the focal plane shutters flash weakness. Leaf shutters don't need HSS. Notice the builtin Q flash can sync at 1/1000. In theory, the add on flashes should also be able to sync at 1/1000. Do not know why they don't - perhaps the timing in the flash needs to be different. Pentax flashes don't appear to be updatable by firmware. These flashes were designed before Pentax had lots of leaf shutter lenses scurrying around. New flashes might
solve this problem.
thanks
barondla

Last edited by barondla; 11-15-2012 at 07:03 AM.
11-16-2012, 07:11 AM   #34
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Thanks, but no need to explain HSS and leaf vs. focal plane shutters to me. You make a good point though that I'd forgotten about -- that Q can sync faster with built-in flash. I guess that's a nice feature but inability to do this with off-camera or more powerful flashes significantly reduces the leaf shutter benefit. Possibly the HSS strobing is tuned for the FP shutter and produces inconsistent results with the LS though I can't say I really understand the exact mechanics of why this would be. Furthermore, Pentax has chosen not to allow their electronic shutter to improve sync speed either, which some Nikon DSLR models of the past did.

I'm not real familiar with MF systems and their more elaborate LS setups but they usually manage at least 1/500 which is great, especially considering that their focal plane shutters may only offer max sync of 1/60-1/125.

11-19-2012, 07:05 PM - 1 Like   #35
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Just wanted to chime in that I received my Q-K adapter today from Crutchfield as well and I am impressed. Although the cost of the adapter is high, it is well worth it if you have a Q and plan to use any K mount lenses. I have the old adapters that were on Ebay but the Pentax one is thinner and outperforms in image quality against all of them. I was very surprised as I don't normally shoot with the Q and K lenses as some of the images can be low quality but with the new adapter everything has improved. The contrast and sharpness are much better and the aperture control ring works much better to let the right amount of light in. With the old adapter I always had a bit of trouble with some lenses. Overall glad I bought the new version as it now lets me get very high quality photos from the K lenses on the Q.
11-19-2012, 08:07 PM   #36
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QuoteOriginally posted by knightzerox Quote
Just wanted to chime in that I received my Q-K adapter today from Crutchfield as well and I am impressed. Although the cost of the adapter is high, it is well worth it if you have a Q and plan to use any K mount lenses. I have the old adapters that were on Ebay but the Pentax one is thinner and outperforms in image quality against all of them. I was very surprised as I don't normally shoot with the Q and K lenses as some of the images can be low quality but with the new adapter everything has improved. The contrast and sharpness are much better and the aperture control ring works much better to let the right amount of light in. With the old adapter I always had a bit of trouble with some lenses. Overall glad I bought the new version as it now lets me get very high quality photos from the K lenses on the Q.
High praise indeed, thanks for sharing your impressions.
11-19-2012, 08:09 PM   #37
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Knightzerox is correct. The Pentax adapter has better image quality than a stock aftermarket adapter. The Pentax adapter is built to the quality levels of the Q.
thanks
barondlA
11-19-2012, 08:11 PM   #38
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QuoteOriginally posted by barondla Quote
Knightzerox is correct. The Pentax adapter has better image quality than a stock aftermarket adapter. The Pentax adapter is built to the quality levels of the Q.
thanks
barondlA
Is the image quality superior to the stock aftermarket adapters but on par with them once they are modified, or is it clearly superior in IQ to the aftermarket adapters even when they have been modified?

11-19-2012, 08:44 PM   #39
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QuoteOriginally posted by barondla Quote
Knightzerox is correct. The Pentax adapter has better image quality than a stock aftermarket adapter. The Pentax adapter is built to the quality levels of the Q.
thanks
barondlA
Could you (or someone else) post pictures to compare please ?
Thanks.
11-19-2012, 08:47 PM   #40
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QuoteOriginally posted by AndrewG NY Quote
You make a good point though that I'd forgotten about -- that Q can sync faster with built-in flash. I guess that's a nice feature but inability to do this with off-camera or more powerful flashes significantly reduces the leaf shutter benefit. Possibly the HSS strobing is tuned for the FP shutter and produces inconsistent results with the LS though I can't say I really understand the exact mechanics of why this would be. Furthermore, Pentax has chosen not to allow their electronic shutter to improve sync speed either, which some Nikon DSLR models of the past did.
.
Hi Andrew,

I believe that the sync speed limitation is indeed in the external flashes. Pentax has traditionally been at the slow end of flash sync speed, and some of the film bodies were even slower than the DSLRs, so I'm sure the protocols for their external flashes aren't the most optimal. Other brand flashes might produce higher sync speeds, but I'm sure that Pentax only tests and specs with their own external flashes.

The electronic shutter sync is something else. The early Nikon DSLRs that allowed very high sync speeds were using CCD sensors, and electronic shutters with this technology are relatively easy since the whole sensor dumps at once to clear before exposure, then all the individual light sensors can be turned off at once to end an exposure, after which the whole sensor's data is dumped at one time to an external cache. CMOS sensors don't work this way. Data from the light sensors is partially processed on chip and read in sequential rows of pixels, which takes time. This is why CMOS sensors are prone to the rolling shutter effect (jello effect) for moving subjects. There might be some tech out there that can turn all the light sensors off at the same time on a CMOS sensor, but it apparently isn't built into the BSI CMOS sensor that Sony or whoever supplies to Pentax for the Q. this is not Pentax's choice -- it's a limitation of the technology.

I agree that they should have included advanced flash options like remote wireless TTL capability if it was indeed possible, but it might not be. This requires some significant high speed processing (four back and forth flash sequences between the flash and the camera body), and the Q's processing power might be somewhat limited by size. I'd be happy if they'd just upgrade the flash performance with external flash to industry standard for cameras with a hot shoe.

Scott
11-19-2012, 08:49 PM   #41
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QuoteOriginally posted by Docrwm Quote
Is the image quality superior to the stock aftermarket adapters but on par with them once they are modified, or is it clearly superior in IQ to the aftermarket adapters even when they have been modified?
I have two of the older adapters but I haven't modified them in anyway. I can post some sample pictures in a comparison tomorrow when I get a chance. Thanks.
11-19-2012, 09:49 PM   #42
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QuoteOriginally posted by knightzerox Quote
I have two of the older adapters but I haven't modified them in anyway. I can post some sample pictures in a comparison tomorrow when I get a chance. Thanks.
Thanks, I have an unmodified one as well. I appreciate your offering and would be interested in any meaningful differences based on brand, aperture control, etc.
11-19-2012, 10:22 PM   #43
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QuoteOriginally posted by Docrwm Quote
Is the image quality superior to the stock aftermarket adapters but on par with them once they are modified, or is it clearly superior in IQ to the aftermarket adapters even when they have been modified?
Haven't shot the 3rd party adapter since getting the Pentax made one. My hunch is the Pentax will still win the IQ race by a hair. This is based on a few points.

1. Pentax adapter probably has less reflections than a garage painted adapter. There are special antireflection paints used for optical devices. We used flat matte black from a hardware store to modify the 3rd party adapter.

Aftermarket adapter is cone shaped which is more likely to focus light right back at the sensor. Pentax adapter is tube shaped and has different diameter internal chambers, which most likely break the light up more. Pentax adapter also has antireflection ridges in places.

2. Optional Pentax tripod foot is much sturdier than modified foot of 3rd party adapter.

3. 3rd party adapter forces cruder aperture adjustments. 1 stop on the clicks- sometimes 1/2 stops are possible without faling between clicks. Pentax adapter is infinetly adjustable.

4. Precision. My 3rd party adapter has a tripod foot that is out of alingment with horizon. Hear some don't focus to infinity.

Will try to shooting a comparison when time allows.
thanks
barondla
11-19-2012, 10:29 PM   #44
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QuoteOriginally posted by barondla Quote
Haven't shot the 3rd party adapter since getting the Pentax made one. My hunch is the Pentax will still win the IQ race by a hair. This is based on a few points.

1. Pentax adapter probably has less reflections than a garage painted adapter. There are special antireflection paints used for optical devices. We used flat matte black from a hardware store to modify the 3rd party adapter.

Aftermarket adapter is cone shaped which is more likely to focus light right back at the sensor. Pentax adapter is tube shaped and has different diameter internal chambers, which most likely break the light up more. Pentax adapter also has antireflection ridges in places.

2. Optional Pentax tripod foot is much sturdier than modified foot of 3rd party adapter.

3. 3rd party adapter forces cruder aperture adjustments. 1 stop on the clicks- sometimes 1/2 stops are possible without faling between clicks. Pentax adapter is infinetly adjustable.

4. Precision. My 3rd party adapter has a tripod foot that is out of alingment with horizon. Hear some don't focus to infinity.

Will try to shooting a comparison when time allows.
thanks
barondla
As always, thanks for the thoughtful and detailed reply.
11-20-2012, 08:05 AM   #45
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QuoteOriginally posted by snostorm Quote
I believe that the sync speed limitation is indeed in the external flashes.
Pentax offered 1/250 on the PZ-1, PZ-1p, Z-5, and Z-5p, though these were not P-TTL. They also supported 1/500 when using LS lenses on their MF systems, though not with TTL flash metering. You may be on to something though--maybe the HSS workaround also liberates them from more precise timing speeds quicker than 1/250 would require, though again it's a shame that the Q doesn't support this.

QuoteOriginally posted by snostorm Quote
Other brand flashes might produce higher sync speeds.
But we'll never know because when flash is connected shutter speed is limited in firmware (not sure what would happen if a 'dumb' PC-sync flash was connected).

QuoteOriginally posted by snostorm Quote
I agree that they should have included advanced flash options like remote wireless TTL capability if it was indeed possible, but it might not be. This requires some significant high speed processing (four back and forth flash sequences between the flash and the camera body), and the Q's processing power might be somewhat limited by size.
I don't know how significant. Pentax managed to include it in the MZ-6 / ZX-L circa 2001 which contains processing power well south of what is required to record HD video and offer speedy contrast-detect AF. Plus, the same limitations are in place when the external flashes are mounted on the hotshoe or wired via TTL sync cable, so it's not just wireless.

QuoteOriginally posted by snostorm Quote
I'd be happy if they'd just upgrade the flash performance with external flash to industry standard for cameras with a hot shoe.
Well they sort of have -- they're offering 1/250 on the Q (but again, no HSS). It's the DSLRs of course we should be complaining about.
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