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04-20-2016, 06:30 AM   #46
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QuoteOriginally posted by whwang Quote
What's worse, way worse, is that the A7X series try to filter out hot pixels during long exposures taken in the Bulb mode. This simultaneously filters out stars, and this cannot be turned off. See an example of mine made with A7R and Sigma 50/1.4, where many stars in the top two frames disappear:



This problem can only be avoided by taking exposures in the M mode, and therefore the exposure time can't be longer than 30 sec. To achieve a deep image, one has to take many many 30 sec exposures, instead of, for example, just tens of 5 minute exposures. This significantly increases the post-processing time, and the size of the memory card. Also, this leads to compromised image quality if one takes pictures under very dark sky, where longer exposures (of single images, not total integrated exposure) are required to completely eliminate the readout noise of the camera.

This is the same mistake Nikon made 10 years ago, and this is one of (if not THE one) the key reasons that lead to Canon's dominance in amateur astrophotography. Now Sony makes the same mistake again. People complain to Sony about this for more than a year, and there is no sign that Sony is going to address this any time soon.
Unless it has changed in the last two firmware updates that I haven't applied yet for my A7RII, you can turn off Long exposure noise reduction. Even in Bulb.You will end up with hot pixels on very long exposures (the 645Z handles this better in my opinion).

---------- Post added 04-20-16 at 06:35 AM ----------

Perhaps the updated 75 f/2.8 might become a larger 75 f/2. That's a possibility. On the wide angle front that will be challenging. The 28 - 45 is huge and heavy at f/4.5. The 25 bulky with a bulbous front which makes the use of graduated filters difficult. A 21 - 24mm prime would be fantastic but anything faster than f/4 will mean you will need to be built like Mr Universe to carry it around. To help, they could do without the SR. Or bring SR to the body in its next iteration. I have preordered the Batis 18 for the Sony and will most likely sell my DFA 35 to cover the cost, now that I have a 28 - 45 again.

Personally I don't get the fascination with only being able to get 1 hair in focus wide open, but that's just me - I do very little in the way of portraiture. The most I see online is poorly used just to say "look at what I shot wide open!". The way Gavincato uses it is great of course...


Last edited by itshimitis; 04-20-2016 at 06:40 AM.
04-20-2016, 07:04 AM   #47
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QuoteOriginally posted by itshimitis Quote
Unless it has changed in the last two firmware updates that I haven't applied yet for my A7RII, you can turn off Long exposure noise reduction. Even in Bulb.You will end up with hot pixels on very long exposures (the 645Z handles this better in my opinion).[COLOR="Silver"]
What I said has nothing to do with the long exposure NR that users can turn off in the menu. It can't be turned off. It's always automatically on in Bulb mode. You can use "Nikon mode 3" as keywords to make a google search and see the long history of this. The same is now happening on the A7x series.

People who do serious astrophotography rarely worry about hot pixels. We always turn off long exposure NR and take dark exposures afterward. The subtraction of hot pixels and thermal signal can be done in post processing. This saves the precious night time. We want to spend as much time as possible to collect photons, rather than using 1/2 of the time on the in-camera long exposures NR.
04-20-2016, 07:50 AM   #48
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QuoteOriginally posted by whwang Quote
What I said has nothing to do with the long exposure NR that users can turn off in the menu. It can't be turned off. It's always automatically on in Bulb mode. You can use "Nikon mode 3" as keywords to make a google search and see the long history of this. The same is now happening on the A7x series.

People who do serious astrophotography rarely worry about hot pixels. We always turn off long exposure NR and take dark exposures afterward. The subtraction of hot pixels and thermal signal can be done in post processing. This saves the precious night time. We want to spend as much time as possible to collect photons, rather than using 1/2 of the time on the in-camera long exposures NR.
Well when I took this shot with the A7RII:



I didn't have LENR on and it didn't do it either...
04-20-2016, 08:52 AM   #49
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Hi, What you really need to do is to shot point-like objects, not star trails. I don't think the effect will have big impact to star trail pictures, since star trail do not look like hot pixels at all.

Find a tracker and do a good alignment. Take a raw picture of 30-second bulb, and then 30-second M, everything else the same. Compare the two pictures carefully, and you will know what I was talking about.

BTW, your lens needs to be sharp. If the lens is not sharp, the stars do not look like hot pixels and your camera wouldn't want to erase those stars.

04-20-2016, 09:39 AM   #50
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QuoteOriginally posted by whwang Quote
Hi, What you really need to do is to shot point-like objects, not star trails. I don't think the effect will have big impact to star trail pictures, since star trail do not look like hot pixels at all.

Find a tracker and do a good alignment. Take a raw picture of 30-second bulb, and then 30-second M, everything else the same. Compare the two pictures carefully, and you will know what I was talking about.

BTW, your lens needs to be sharp. If the lens is not sharp, the stars do not look like hot pixels and your camera wouldn't want to erase those stars.
My point was that the long exposure noise reduction. It didn't operate in the shot above and it was on bulb
04-20-2016, 12:47 PM   #51
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@ Pål Jensen: Can you elaborate what you mean by "better image quality"? I think that might be the point we don’t understand each other.

FF with f/2,2 gives the same DoF as 645Z with f/2,8 (with same shutter speed and equivalent, not equal, focal lengths. For instance 35mm on FF vs 45mm on 645Z)
FF with f/2,2 ISO 1600 gives the same noise level as 645Z with f/2,8 ISO 2500 (with same shutter speed and equivalent, not equal, focal lengths. For instance 35mm on FF vs 45mm on 645Z)

I'm not trying to normalise everything into one format. This is just relative numbers and can just as well be viewed the other way around. Or use APS-C as a comparative base.

---------- Post added 04-20-16 at 10:03 PM ----------

QuoteOriginally posted by itshimitis Quote
Personally I don't get the fascination with only being able to get 1 hair in focus wide open, but that's just me - I do very little in the way of portraiture.
I totally agree on that. Its the same thing with macro photo only to a larger extent. Even f/22 can be way to short DoF. But when shooting larger subjects like buildings, bridges, water falls, night landscapes reflected in water and such, the DoF will be more then sufficient even at f/1,2. If there are moving subjects in the scene simultaneously, like clouds, large apertures are wanted for its light gathering capability (fast shutter combined with low ISO). These are examples where large aperture FF wins on noise and/or shutter speed over the current cropped 645 format.

Last edited by Simen1; 04-20-2016 at 01:07 PM.
04-20-2016, 04:42 PM   #52
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QuoteOriginally posted by itshimitis Quote
Personally I don't get the fascination with only being able to get 1 hair in focus wide open, but that's just me - I do very little in the way of portraiture. The most I see online is poorly used just to say "look at what I shot wide open!". The way Gavincato uses it is great of course...
guilty I've always been a shallow dof guy. even before i knew what i was doing 10 years ago i was shooting a nikon & a 85/1.4 lens for 90% of a wedding.

A lot of guys just shoot with thin dof and expect the photo to be good. the trick is knowing how the backgrounds will render per lens and choosing backgrounds that render out of focus well. This is where guys like jose villa whip butt. I'n trying
04-20-2016, 04:50 PM   #53
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QuoteOriginally posted by itshimitis Quote
My point was that the long exposure noise reduction. It didn't operate in the shot above and it was on bulb
I think we all know that the normal long exposure NR can be turned off. And it's not the point at all. There is another kind of noise reduction that still acts on your image and it can't be turned off. You didn't notice it because it is a star trail photo, but it has strong impact to other kinds of astrophotography.

04-27-2016, 03:26 AM   #54
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until the 645's increase sales by 200-500% lenses under f2.0 are a pipe dream.tryng to have mf lenses that match fx and dx lenses is just not realistic. the cost would be through the roof.
04-27-2016, 05:52 AM   #55
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Do you think e.g. Schneider Kreutznach or Leica don't sell any lense yet ?
You cannot avoid f/2 in medium format if you talk about "uncompromising IQ".
04-27-2016, 06:13 AM   #56
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QuoteOriginally posted by bull drinkwater Quote
until the 645's increase sales by 200-500% lenses under f2.0 are a pipe dream.tryng to have mf lenses that match fx and dx lenses is just not realistic. the cost would be through the roof.
Thats a chicken and egg question. How can the 645 grow without improvements when FF is outperforming it in key areas and that for a considerable lower price?

645 needs both larger sensor and larger apertures to combat the competition from below. I doubt Pentax would want to cannibalize the 645 line with K-1 sales. Therefore I believe improvements are on its way.
04-27-2016, 11:12 PM   #57
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QuoteOriginally posted by Simen1 Quote
Thats a chicken and egg question. How can the 645 grow without improvements when FF is outperforming it in key areas and that for a considerable lower price?

645 needs both larger sensor and larger apertures to combat the competition from below. I doubt Pentax would want to cannibalize the 645 line with K-1 sales. Therefore I believe improvements are on its way.

we are talking a limited market here. the number of people able and willing to pay $7000.00 or more for a camera will never match regular camera sales. the number of people willing to pay $8000.00-$10,000.00 [ wich they would have to cost ] for an f i.8 lens wouldn't justify the research let alone the production . just my opinion.
04-28-2016, 01:07 AM   #58
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You indirectly say that Pentax should should reduce their 645 sales to the number of irrational thinking customers. Hasselblad Lunar and Stellar should indicate the market size and economic future. Hasselblad wisely chose to stop loss on this ridiculous project.

If Pentax have to triple the price for the camera and lens to make it possible, thats still way cheaper then comparable Hasselblad and Phase One models and a necessity to make 645 a rational choice for the most quality demanding.

There is hardly any rational reasons left to pay extra for a 645Z with the current lenses in stead of just buying a K-1 with large aperture lenses. Thats a sad fact and I hope and believe Pentax will do something about it. Even if they have to triple the price. The 645 system deserves better then a gravestone.
04-28-2016, 03:03 AM   #59
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QuoteOriginally posted by Simen1 Quote
You indirectly say that Pentax should should reduce their 645 sales to the number of irrational thinking customers. Hasselblad Lunar and Stellar should indicate the market size and economic future. Hasselblad wisely chose to stop loss on this ridiculous project.

If Pentax have to triple the price for the camera and lens to make it possible, thats still way cheaper then comparable Hasselblad and Phase One models and a necessity to make 645 a rational choice for the most quality demanding.

There is hardly any rational reasons left to pay extra for a 645Z with the current lenses in stead of just buying a K-1 with large aperture lenses. Thats a sad fact and I hope and believe Pentax will do something about it. Even if they have to triple the price. The 645 system deserves better then a gravestone.
Are you suggesting there is no difference between an image from the K1 and 645Z? If so, prove it. If there is difference, then it is up to Ricoh's marketing department to make the most of it. That's their remit after all.

The difficulty with your suggestion is badge snobbery. People being prepared to pay 2 - 3 times the current price of the Z for a full frame 645 can probably afford a lower megapixel hassle or P1. Top professionals often lease their cameras, so could end up getting a Hassie or P1 on lease.

Bull Drinkwater is saying to reduce the sales to rational thinking customers. The sheep in wolves' clothing that was the Stellar etc failed because the people who knew Hassie weren't fooled and the fact that most people are more clued up tech wise, a quick search showed these cameras for what they were, and they weren't Hassies.

In the same way from my recollection, the original Pentax 645 system was intended to be medium format, not for the masses but for those who didn't have the resources for the more expensive systems. To go above a certain level pricewise risks the camera being taken to nomansland. At the $30k level, choices are different. Lens prices have already got very high.

I'm not sure it would serve Pentax's interests to take the 645 where it doesn't quite fit. Yes it holds its own against many of P1/H's more entry level camera - in fact some might suggest it more than holds its own. Being too expensive for the market it has now, but not highly enough thought of for the highest end would be very bad for the system in my view.
04-28-2016, 03:12 AM   #60
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QuoteOriginally posted by Simen1 Quote
You indirectly say that Pentax should should reduce their 645 sales to the number of irrational thinking customers. Hasselblad Lunar and Stellar should indicate the market size and economic future. Hasselblad wisely chose to stop loss on this ridiculous project.

If Pentax have to triple the price for the camera and lens to make it possible, thats still way cheaper then comparable Hasselblad and Phase One models and a necessity to make 645 a rational choice for the most quality demanding.

There is hardly any rational reasons left to pay extra for a 645Z with the current lenses in stead of just buying a K-1 with large aperture lenses. Thats a sad fact and I hope and believe Pentax will do something about it. Even if they have to triple the price. The 645 system deserves better then a gravestone.
hilarious, the k1 hasn't even shipped and it's already at 645z level
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