Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-21-2016, 04:31 AM   #16
Junior Member




Join Date: Mar 2016
Posts: 33
QuoteOriginally posted by peterm1 Quote
...I am finding it noticeably easier to blow highlights than on my other cameras and am finding myself adjusting exposure compensation downward severely. Given that the camera is known for its dynamic range I am a bit surprised at how easy it is to blow highlights that can't be recovered in Lightroom. Are most people finding this to be the case, and any tips for how to deal with this except dialing down exposure compensation?
Yes, after 8 years shooting a Canon 5D Mark II as my main camera, I had the same "issue" with he 645z for the first few days. I would get the RAWs into Lightroom and find I hit highlight recovery much sooner than I would expect.

It was only after I did some detailed testing, i.e. measuring with a handheld light meter, shooting 50% grey cards, shooting a white towel in the sun and then looking at the histogram to understand the scale was I able to understand what was happening.

What I found was, using the Normal scene rendering mode, the middle vertical line is 50% grey, the first vertical line is +1.5EV, and the last vertical line is +3EV. There is about 1/2 to 1 stop available past that depending on ISO and white balance.

The 645Z histogram range is so large compared to what I was used to, that I was exposing to the right way more than I thought I was. It took a few days to get used to the new histogram - I always thought I was underexposing when I was just reading the histogram wrongly.

04-21-2016, 06:39 AM   #17
Veteran Member
Kolor-Pikker's Avatar

Join Date: Dec 2014
Posts: 341
QuoteOriginally posted by glass Quote
Yes, after 8 years shooting a Canon 5D Mark II as my main camera, I had the same "issue"
I came from the 5DII as well, was surprised by this fact initially as well. Back when Capture One 7 came out with the enhanced recovery tools, I was able to pull a massive amount of highlight detail from the 5D, but dialing -10 HR in Lightroom is the extent of what can be done on the Z before you start generating false colors. Even so, the Z has considerably more total DR than the 5D had, it's just all bunched up in the shadows.

Post-wise, the problem this creates is that Lightroom sometimes doesn't provide enough shadow recovery, so you end up having to raise the overall exposure and then pull down the highlights if they get blown out. Just a bunch of extra steps to take to get everything to "fit in" so to speak, so it's worth making a few presets, especially since by default the contrast, saturation, and sharpening are set too low.
04-21-2016, 08:07 AM   #18
Junior Member




Join Date: Mar 2016
Posts: 33
QuoteOriginally posted by Kolor-Pikker Quote
I came from the 5DII as well, was surprised by this fact initially as well. Back when Capture One 7 came out with the enhanced recovery tools, I was able to pull a massive amount of highlight detail from the 5D, but dialing -10 HR in Lightroom is the extent of what can be done on the Z before you start generating false colors.
Yes, Adobe's 645z highlight recovery is like falling off a cliff, whereas 5DII highlight recovery is a lot more friendly. The best highlight recovery I've ever used is with Sigma's Foveon sensors (using Sigma's own Photo Pro).
04-21-2016, 09:15 AM   #19
Senior Member




Join Date: Feb 2016
Posts: 181
I believe you will find that different camera manufacturers and different raw application developers may have very different views on how much headroom to give for raw exposures therefore we can believe that we are pulling back an awful lot of detail at the highlight end and it is solely due the camera. This may not be the real case.

Taking Adobe LR and ACR first, they produce raw format profiles for hundreds of cameras and during the raw rendering set what they deem to be a reasonable first view of the raw image data. This rendering will include tweaks to the brightness, contrast and any other parameters that Adobe see fit to change to make either a neutral or, in their view pleasing rendering (not necessarily accurate!). These 'tweaks' are done under the hood and will not display on the sliders (they will remain at default positions). Therefore you will not necessarily know what is happening to the original raw data unless you start digging. There is nothing wrong with this approach, I believe that many raw converters will apply their own tweaks - including even sharpening and noise reduction before presentation as a default on your screen.

Well, actually there may be a problem with this approach at least in my view. That problem is that it is quite possible that someone could take the view that as their raw editor shows a bunching up of values to the right of the histogram that they must be overexposing and then take action to apply negative exposure compensation. The potential result being that they could be underexposing maybe by up to two stops, pushing the shadow values down too far to enable decent recovery and consequently losing IQ.

At this time with only a play with metering on the 645, I believe it is doing its job correctly and seeing the 'correct' values that fall within the ISO/ANSI standards for exposure meters. Checking against my Sekonic spotmeter there is a difference of 1/3 EV between the two when metering of a neutral grey card. Sekonic meter calibration happens to be K=12.5 therefore I am guessing that Pentax are probably where they used to be at K=14.0.

In any case using either meter we should expect the histogram spike to be left of centre for JPEG and even more for raw (assuming that centre camera histogram represents 50% brightness).

Taking a shot of my test card metering on the grey card in centre with camera meter set to spot (matrix and centre gave the same result as expected) gave 1/2 sec, f/8 @ 100 ISO. The Sekonic suggested f/9.

Notice the difference between FastRaw Viewer and ACR highlighting the difference that a raw converter can make - Raw Therapee (not shown shows the same). It seems to me that in this case there is a degree of under rather than overexposure and I will test again just to confirm that I have not made any input errors

Attached Images
 
04-21-2016, 09:18 AM   #20
Site Supporter
mikeSF's Avatar

Join Date: Jan 2009
Location: East Bay Area, CA
Photos: Gallery
Posts: 5,680
QuoteOriginally posted by 2351HD Quote
Mike I am curious, does the metering setting even matter if you shoot in M mode with live view and live histogram using manual adjustments? I would have thought not?
I am still using green button to set a shutter speed or at least reading the exposure meter bars. Unless I am not understanding what you are asking me?

Most commonly for landscape shooting (single exposure), i frame the shot, turn on the camera and focus with LV, turn off LV. Set aperture, press green button to get a suggested shutter speed. If i know by eye that i want to bring up or down exposure from what the camera is likely seeing, i may click my shutter speed 2 or 3 clicks up or down without using live histogram nor shooting a test shot. Then fire.

In a still life or controlled light situation, I will take more time, use the live histogram, but in the field, i have gotten comfortable looking at my scene, evaluating the relative quantity of light values, and knowing pretty well how the camera is going to meter and how the histogram is going to look.

I am such a control freak that i don't want the camera making any decisions for me, only "suggestions". I make the decisions.
04-21-2016, 10:11 AM   #21
Pentaxian




Join Date: Apr 2014
Location: Baltimore
Posts: 529
QuoteOriginally posted by Kolor-Pikker Quote
It would be optimal if Pentax adjusted via firmware the system's idea of where middle gray should be in the DR scale, so that you have an even amount of shadow and highlight headroom.
Yes, exactly.

---------- Post added 04-21-16 at 01:13 PM ----------

QuoteOriginally posted by glass Quote
Yes, after 8 years shooting a Canon 5D Mark II as my main camera, I had the same "issue" with he 645z for the first few days. I would get the RAWs into Lightroom and find I hit highlight recovery much sooner than I would expect.

It was only after I did some detailed testing, i.e. measuring with a handheld light meter, shooting 50% grey cards, shooting a white towel in the sun and then looking at the histogram to understand the scale was I able to understand what was happening.

What I found was, using the Normal scene rendering mode, the middle vertical line is 50% grey, the first vertical line is +1.5EV, and the last vertical line is +3EV. There is about 1/2 to 1 stop available past that depending on ISO and white balance.

The 645Z histogram range is so large compared to what I was used to, that I was exposing to the right way more than I thought I was. It took a few days to get used to the new histogram - I always thought I was underexposing when I was just reading the histogram wrongly.
hmmm, very interesting
04-22-2016, 01:57 PM - 1 Like   #22
Pentaxian




Join Date: Apr 2013
Location: Brisbane, Australia
Posts: 619
Mike, I never knew that's what the green button did!

I set exposure manually in live view using the histogram for all tripod work, I frame using live view and then fire off some test shots till I get it right. This is usually 2-3 images before I get it exact. Then I sit there and wait till the light is right, sometimes chasing the histogram on screen with the shutter dial as the light either gets lower or higher, until the shot I want presents itself.
04-22-2016, 03:57 PM - 1 Like   #23
Loyal Site Supporter
unkipunki's Avatar

Join Date: Dec 2012
Location: South Lochaweside, Argyll
Photos: Gallery
Posts: 538
QuoteOriginally posted by mikeSF Quote
I am still using green button to set a shutter speed or at least reading the exposure meter bars. Unless I am not understanding what you are asking me?

Most commonly for landscape shooting (single exposure), i frame the shot, turn on the camera and focus with LV, turn off LV. Set aperture, press green button to get a suggested shutter speed. If i know by eye that i want to bring up or down exposure from what the camera is likely seeing, i may click my shutter speed 2 or 3 clicks up or down without using live histogram nor shooting a test shot. Then fire.

In a still life or controlled light situation, I will take more time, use the live histogram, but in the field, i have gotten comfortable looking at my scene, evaluating the relative quantity of light values, and knowing pretty well how the camera is going to meter and how the histogram is going to look.

I am such a control freak that i don't want the camera making any decisions for me, only "suggestions". I make the decisions.
Snap. My field approach exactly.

04-22-2016, 05:00 PM   #24
Site Supporter
mikeSF's Avatar

Join Date: Jan 2009
Location: East Bay Area, CA
Photos: Gallery
Posts: 5,680
QuoteOriginally posted by 2351HD Quote
Mike, I never knew that's what the green button did!

I set exposure manually in live view using the histogram for all tripod work, I frame using live view and then fire off some test shots till I get it right. This is usually 2-3 images before I get it exact. Then I sit there and wait till the light is right, sometimes chasing the histogram on screen with the shutter dial as the light either gets lower or higher, until the shot I want presents itself.
i never even usually have to look at a test shot because the metering is so predictable. In fact, i have come home from shooting before not knowing my WB was set to tungsten, for example, because i never chimped. I like to be surprised when i get home, lol.

QuoteOriginally posted by unkipunki Quote
Snap. My field approach exactly.
Sweet. I find if i stick to with a process, i never forget anything...and minimal surprises when getting home, lol.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
645d, 645z, blow, camera, compensation, days, exposure, feathers, forum, histogram, iso, line, medium format, middle, mode, poster, reflection, scale, subject, sunlight, tav, thanks, time, view
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to avoid blowing highlights / what are your settings? (WG-4) sameagle Pentax Compact Cameras 1 07-07-2015 10:54 AM
Phillip Bloom added 100+ photos from his 645Z on Facebook MyTZuS Pentax Medium Format 4 03-04-2015 09:50 PM
Travel Highlights from Europe chunhin Post Your Photos! 3 08-12-2013 01:19 AM
Clipped highlights on the Q. GibbyTheMole Pentax Q 18 06-11-2013 11:51 AM
K5 & blowing out the highlights BLW44 Pentax K-5 29 10-10-2011 03:10 AM



All times are GMT -7. The time now is 09:45 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top