Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version 22 Likes Search this Thread
08-29-2020, 04:24 PM   #1
Loyal Site Supporter
Loyal Site Supporter




Join Date: Sep 2015
Posts: 10
Why can't my KP photograph a rainbow?

Tried taking a photo of a glorious rainbow with my KP and the Pentax 12-24 mm wide angle. Just the UV filter on the lens. All I got was shades of grey (with a hint of colour) for the rainbow. Had to get out my iPhone X to take take the shots. What's the problem? - love to know.

Attached Images
View Picture EXIF
PENTAX KP  Photo 
View Picture EXIF
PENTAX KP  Photo     
08-29-2020, 04:36 PM   #2
Senior Member




Join Date: Feb 2012
Photos: Gallery
Posts: 143
i would start with removing UV filter. I suppose you're shooting raw and adjust in post everything. plus i think that your focus is off. But than again I think that iOS has machine learned AI that enhances certain details that it recognises so it produces a flawless rainbow in your case.
08-29-2020, 04:37 PM - 1 Like   #3
Pentaxian




Join Date: May 2016
Photos: Gallery
Posts: 3,726
It has to do with how it's processed. By default, phone photos have much higher saturation, contrast, sharpening, to make them look "punchy".
Also, the images from the KP are exposed brighter so that washes out the rainbow a bit because, but in general, Pentax jpegs are more muted. You can do the same by taking the time to configure your camera's jpeg output, or editing raws; the in-camera jpeg settings are quite flexible, but still likely to not go as far as phone pictures.

edit: The exif in your images also shows as manually set, and it's quite warm, that will also affect how the rainbow contrasts the sky. I've tried getting the rainbow to show more in the jpeg, and it required also cooling in addition to lower brighteness and more saturation. Not worth posting because, being jpegs, it shows banding quickly with such large changes.

Last edited by aaacb; 08-29-2020 at 04:55 PM.
08-29-2020, 04:53 PM   #4
Pentaxian




Join Date: May 2016
Photos: Albums
Posts: 2,003
Possibly wrong auto WB?

08-29-2020, 05:15 PM - 3 Likes   #5
Moderator
Loyal Site Supporter
Loyal Site Supporter
pschlute's Avatar

Join Date: Mar 2007
Location: Surrey, UK
Photos: Gallery
Posts: 8,216
Manual white balance....centre weighted metering ? You have overexposed the first two shots.
08-29-2020, 05:17 PM   #6
Site Supporter
Site Supporter
ramseybuckeye's Avatar

Join Date: Apr 2009
Location: Hampstead, NC
Photos: Gallery
Posts: 17,295
I would probably change my metering to multi as opposed to the center weighted that you used. I agree with leekil on the WB, I see you were on manual white balance, did you set it for this photo? I can’t think of a more perfect situation for multi auto white balance. I think it is quite likely over exposed also, auto exposure sometimes does that. I would ditch the UV filter also, I’m not sure if it could alter a rainbow, but it definitely can’t improve it. Hopefully you were using the hood, because that definitely is important and a lack of a hood would seriously kill your contrast.

Also, I cannot tell by the exif what you have set in the custom image setting, they can make a big difference, which if the wrong one is set, it can be fixed when you shoot raw.

Last edited by ramseybuckeye; 08-29-2020 at 05:59 PM.
08-29-2020, 06:33 PM   #7
Custom User Title
Loyal Site Supporter
FozzFoster's Avatar

Join Date: Jan 2016
Location: Alberta
Photos: Albums
Posts: 6,808
I see you shot at 1/1000.
Given the subject isn't moving, I would have dropped that down ~3 stops.
I would have put that extra light into lowerin my ISO and probably stopping down the aperture a click or two.
As other mentioned, what washed your image out was the center metering and manual white balance.. set those to multi and auto.
Also shoot in RAW and you can edit these much easier.

08-29-2020, 06:37 PM   #8
Moderator
Loyal Site Supporter
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 15,987
You are several stops over exposed.
08-29-2020, 11:19 PM - 4 Likes   #9
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 42,007
There are some good observations above, though I will weigh in too. The EXIF metadata indicates that you were shooting RAW. That is a good thing, because it give you a lot of latitude in post-processing. The ITPC/XMP segment tells me that you are using Adobe Lightroom to process your DNG files. That is also a good thing, since Lightroom is very powerful and flexible. It also gives details of what was done in processing. While most of the camera settings are not longer in the version displayed with your post, there is still a good amount of useful information. Below are a few notes in regards to the second KP image.

The photo was taken earlier this week, fairly late in the day (~7:00 PM) with exposure settings about three stops over what I would have expected for conditions Auto exposure was being used with no exposure compensation and it is difficult to see what in the frame would have fooled the meter to this extent. Center-weighted, rather than the more sophisticated multi-segment metering shared with the K-1 and K-3, was used. This, in itself is not an explanation, though I would suggest using multi-segment for general shooting. That 88K pixel evaluative RGB sensor is part of the reason for the KP's premium price and worth using.

Several comments were made above regarding manually set white balance. Since you are shooting RAW (DNG), that should not be a major problem in post processing except that Lightroom will use that setting as the base for its initial processing. I don't know what adjustments you might have made within Lightroom as part of your processing except that the final setting was 6200K with +46 tint applied. 6200K may have been appropriate for much of the frame, though less warming (lower number) might have been better. That aside, the +46 tint lends a pretty huge dose of magenta that masks other colors. Both the warming and the magenta are visible in the photo. I suspect that the Lightroom settings reflected those from the camera and that those were accidental and not intended for this photo. Auto white balance is usually a good choice for natural light with the camera usually doing an excellent job. As hinted above, you have the choice when shooting RAW to change the white balance to whatever looks most natural to your eyes. Nothing in the white balance from the camera is permanently "baked" into the capture data.

The rest of the XMP looks to be standard Lightroom defaults. A lot could have been done here to rescue the shot using the Develop module. Suggestions are:
  • Correct the bad white balance using either LR's "auto" feature or the WB "picker"
  • Decrease exposure about 3 stops
  • Increase contrast either with that slider or by judicious increase using the highlight slider. This should provide some pop.
  • Add about 15 units of clarity and about 15 units of vibrance. Doing so will provide additional subtle contrast lift and also a subtle bump to local saturation.
  • If needed, try judicious application of (global) saturation. A little goes a long way here. FWIW, I almost never use the saturation slider, preferring instead to add or subtract further down in the color adjustment panel.
At this point, the result should look a lot more like your intended photo. Of course, there is always more. I like to massage the contrast curve and color balance directly, but that comes with experience.

The big question might be why the base capture was flawed. Why it is overexposed is a puzzle. I would have expected the opposite based on the sun angle except that the distant shore area at center was probably quite dark from the squall. I suspect the white balance was either an accident or was left over from some earlier experiment or was part of a custom image setting accidentally applied.

I used the word "accident" several times, because it is possible to to apply some settings without intending to do so, usually with the base of the thumb on the right hand. At least is how it happens on the K-3/K-3II when such interacts with the 4-way controller. To help avoid accidents from carrying over to another session, I have my K-3 configured to revert to defaults when the camera is turned off for many settings and to "forget" those I don't want the camera to remember for general shooting. The magic is done using:
menu > Rec Mode 5 > Memory
Most are remembered by default, but several can be problematic if remembered. If one needs a particular combination of special settings, saving them to a dedicated user mode is very good.

I hope this helps. Have fun!


Steve

Last edited by stevebrot; 08-30-2020 at 10:03 AM.
08-29-2020, 11:22 PM   #10
Site Supporter
Site Supporter
mike.hiran's Avatar

Join Date: May 2007
Location: portland
Photos: Albums
Posts: 1,491
QuoteOriginally posted by Wheatfield Quote
You are several stops over exposed.
On your Iphone shots, look at how dark the grass is. On the KP, see how bright the grass is? that makes the sky brighter and the rainbow less visible. If you are shooting in AV mode, turn the front dial to the left to adjust your exposure compensation down about 3 stops. In the viewfinder you'll see where it has a # that changes as you turn that wheel - keep turning until you get the shot you want. MAKE SURE you turn this back to zero before you move on otherwise all your shots thereafter will be 3 stops under exposed!!

Get in the habit of reviewing your shots after you take them - if they are too bright, adjust exposure down. If they are too dark, adjust exposure up. You may want to change your exposure mode to center weighted or spot mode too, but first things first. Get to understand exposure and how (and when) to adjust it.
08-30-2020, 03:02 AM   #11
Site Supporter
Site Supporter
pixelsaurus's Avatar

Join Date: Jul 2007
Location: Te Kuiti, NZ
Photos: Gallery | Albums
Posts: 986
I would try a polarizer filter. They can sure crank up the colour. Tips on pictures of rainbows? - PentaxForums.com
08-30-2020, 03:52 AM - 2 Likes   #12
Moderator
Loyal Site Supporter
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 15,987
QuoteOriginally posted by pixelsaurus Quote
I would try a polarizer filter. They can sure crank up the colour. Tips on pictures of rainbows? - PentaxForums.com
Polarizing filters have an annoying habit of making rainbows dissappear.
08-30-2020, 04:43 AM - 1 Like   #13
GUB
Loyal Site Supporter
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 5,760
QuoteOriginally posted by Wheatfield Quote
You are several stops over exposed.
Correct - probably at least 2 stops and pretty well the sole reason the rainbow has been clipped out.
08-30-2020, 07:38 AM   #14
Pentaxian




Join Date: Sep 2006
Location: Mississippi, USA
Photos: Gallery
Posts: 854
Chimp. Take your shot, Chimp it and the Histogram. Adjust and shoot again. Rainbow is Landscape so you have the time for a Chimp and adjust. I do it every time
08-30-2020, 08:24 AM   #15
Loyal Site Supporter
Loyal Site Supporter




Join Date: May 2007
Location: Flagstaff, Arizona
Posts: 1,648
QuoteOriginally posted by Wheatfield Quote
Polarizing filters have an annoying habit of making rainbows dissappear.
Interesting point.

Never though of this before, but rainbows are reflected/refracted sunlight, and those processes do tend to polarize the light.
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!
camera, chimp, exposure, filter, kp, mode, pentax help, photography, post, rainbow, results, scene, time, troubleshooting

Similar Threads
Thread Thread Starter Forum Replies Last Post
KP vs K-70 - to KP or not to KP, that is the question OldChE Pentax DSLR Discussion 28 11-02-2019 05:29 AM
Why Pentax KP? Para que la Pentax KP? ZeaFoto Pentax KP 16 06-14-2018 08:53 AM
Night Why Why Why eccentricphotography Pentax K-3 Photo Contest 3 06-02-2014 09:36 AM
Burning of the Koran ... ! Why? Why? Why? jpzk General Talk 128 09-14-2010 04:45 PM



All times are GMT -7. The time now is 09:46 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