Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-28-2022, 08:58 AM - 2 Likes   #31
Loyal Site Supporter
Loyal Site Supporter




Join Date: Jul 2021
Location: Zuiderkempen - Grote Netewoud - Belgium
Photos: Gallery
Posts: 238
QuoteOriginally posted by kayasaman Quote

though my issue maybe that the object is about as big as the focusing spot and that's what's throwing the AF off??
I think indeed that you need to get closer to your subject if i see the last 3 pics....your hit range will improve if four subject covers more focus points, like the central 5 / 9 points or so, bit camera dependant. Or divide your viewer in 3x3 rectangles, ideally the subject should reasonably fill the central one..otherwise you need to crop too much afterwards impacting quality. A consequence of this rule is that you need to get really close to small birds....and less to larger birds or ....an elephant or so...

For airplanes at low altitude you need to get closer to airport’s approach or take-of routes...for birds you need patience to get close to their habitat, might need to keep low profile or hide, have patience till they come back,
sometimes it is easier if you can start aiming from take off from their nest or other departing point...

One could also try 500mm tele or more, but aiming gets more difficult on moving targets...2.12.0.0


Last edited by mlag; 04-30-2022 at 02:50 AM.
04-28-2022, 10:26 AM - 1 Like   #32
Senior Member




Join Date: Jun 2021
Photos: Albums
Posts: 148
Original Poster
QuoteOriginally posted by DeadJohn Quote
Weevil wrote "Aperture 1/3 to 1 step stop down from max aperture". In that context "max aperture" means the widest and largest aperture which I think is f4.5 for your lens. 1 stop down from that would be f6.3.

You might be fine at f8. Most lenses are sharp there. You get more depth of field than f6.3 which is more forgiving for focus. In dimmer light, though, rather than staying at f/8 and boosting ISO or slowing shutter speed, you can try to change the aperture.

P.S. Aperture f-stops are counterintuitive when learning. Larger numbers = smaller opening.
Yeah.... it's fine. Perhaps it's just a case of understanding how to use the terminology. I was taking it from the perspective of numbering rather size of the diaphragm

---------- Post added 04-28-22 at 10:38 AM ----------

QuoteOriginally posted by Des Quote
I would just add three things to this:
1. The FA*300 is good wide open (f4.5) but a bit better when stopped down (ie narrower aperture) by two-thirds of a stop (f5.6) or one stop (f6.3). That is the sort of stopping down that @Weevil is referring to. (With lower quality lenses you may need to stop down more to get decent resolution.)
2. The difference in depth of field between, say, f5.6 and f8 (one aperture stop) can be significant if the subject is reasonably close (hence more leeway if focus is not perfect) but the significance diminishes as the subject is further away. For example, using the FA*300 on a K-1ii, DOF at 10m to subject is 307mm at f5.6 and 520mm at f8. At 20m to subject it is 1490mm at f5.6 and 2110mm at f8. (https://www.photopills.com/calculators/dof) At that point you would be better to use f5.6 rather than f8 (that is, one stop wider aperture) and reduce the ISO by one stop (ie halve it - e.g 1600 -> 800) or increase the shutter speed by one stop (ie double it - e.g. 1/500th -> 1/1000th).
3. You might already know this, but if you narrow the aperture beyond a certain point, resolution deteriorates because of diffraction. With the FA*300, it probably falls off beyond f8.

BTW, great examples @DeadJohn @Weevil @Redpit
Yeah, once of the tests I made myself ages ago was to shoot a light source. At first wide open then stop down and see how the image behaves. The size of the diffraction spikes was another tell tale sign.

As to DoF, my recent experiments with macro have taught me a lot about using the aperture setting both mechanically and creatively.


With astro imaging it's not so important as you really want to be wide open as much as possible and really only close the blades to get a bit of extra sharpness. Of course the effect this has is to let less light through the lens and into the sensor. Not something you really wana be doing when shooting a remote galaxy 3.5 million light years away.
Though astro is way more technical in terms of equipment and processes used - especially when using flat, bias and dark frames.

---------- Post added 04-28-22 at 10:43 AM ----------

QuoteOriginally posted by mlag Quote
I think indeed that you need to get closer to your subject if i see the last 3 pics....your hit range will improve if four subject covers more focus points, like the central 5 / 9 points or so, bit camera dependant. Or divide your viewer in 3x3 rectangles, ideally the subject should reaonably fill the central one..otherwise you need to crop too much afterwards impacting quality. A consequence of this rule is that you need to get really close to small birds....and less to larger birds or ....an elephant or so...

For airplanes at low altitude you need to get closer to airportís approach or take-of routes...for birds you need patience to get close to their habitat, might need to keep low profile or hide, have patience till they come back,
sometimes it is easier if you can start aiming from take off from their nest or other departing point...

One could also try 500mm tele or more, but aiming gets more difficult on moving targets...

Birds aside, I'm actually just over a take-off route for planes. Though even large planes like the Boeing 777/787 might be still a little small for my 300mm. Maybe 500-600mm focal length might be better from my currently location. Will need to try near the airport for a better experience. I actually would be quite interested to see how my 24mm, 150mm and 300mm behave out there

---------- Post added 04-28-22 at 10:59 AM ----------

Yesterday and today I tried AF again with difference style targets.

I think I'm happy with these guys:

DFA28-105mm @ 105mm. EXIF: 1/2000s, ISO 400, f/8, using internal HDR mode on AUTO

_IMG0804.jpg - Google Drive

I think it's a JAL 777


FA*300mm @ around 65ft/20m, EXIF: 1/1000s, f/8, ISO 6400

_IMG0829.jpg - Google Drive


As I only use M or B modes, I played around the automatic exposure modes today for the first time. This one was either on Av or TAv mode (can't remember exactly).
04-28-2022, 03:06 PM - 1 Like   #33
Des
Loyal Site Supporter
Loyal Site Supporter
Des's Avatar

Join Date: Jan 2014
Location: Sth Gippsland Victoria Australia
Photos: Albums
Posts: 5,772
QuoteOriginally posted by kayasaman Quote
FA*300mm @ around 65ft/20m, EXIF: 1/1000s, f/8, ISO 6400
Nice shot of the fox. If you have the RAW file some PP will really bring it up.

Here's an example where I would say you didn't really need f8 - f5.6 would have given enough DOF at that distance plus a little more separation and would have allowed a lower ISO. (Easy to say with hindsight of course!)

If you had needed to do so you could also drop the shutter speed a bit for a shot like this. With an animal that isn't moving, 1/500th would be adequate - even less if necessary.

Personally I use TAv for shots like this, because I like to tweak both shutter speed and aperture, while capping the ISO within a reasonable band.
04-28-2022, 03:38 PM   #34
Senior Member




Join Date: Jun 2021
Photos: Albums
Posts: 148
Original Poster
QuoteOriginally posted by Des Quote
Nice shot of the fox. If you have the RAW file some PP will really bring it up.

Here's an example where I would say you didn't really need f8 - f5.6 would have given enough DOF at that distance plus a little more separation and would have allowed a lower ISO. (Easy to say with hindsight of course!)

If you had needed to do so you could also drop the shutter speed a bit for a shot like this. With an animal that isn't moving, 1/500th would be adequate - even less if necessary.

Personally I use TAv for shots like this, because I like to tweak both shutter speed and aperture, while capping the ISO within a reasonable band.

Unfortunately for us, foxes are skittish and can run off quickly though not nearly as bad as squirrels. Initially I used 1/15s shutter with ISO at 100 but the little guy came out really blurred from my hands sharking too much even though I had SR enabled.

What do you suggest I do in PP to bring the fox out more?


In RawTherapee I already used AutoLevels, Saturation, Sharpening, Local Contrast, and Vibrance.... anything else I was a little afraid might add extra noise and damage the image quality.

04-28-2022, 06:01 PM - 1 Like   #35
Des
Loyal Site Supporter
Loyal Site Supporter
Des's Avatar

Join Date: Jan 2014
Location: Sth Gippsland Victoria Australia
Photos: Albums
Posts: 5,772
QuoteOriginally posted by kayasaman Quote
Unfortunately for us, foxes are skittish and can run off quickly though not nearly as bad as squirrels. Initially I used 1/15s shutter with ISO at 100 but the little guy came out really blurred from my hands sharking too much even though I had SR enabled.
That's not surprising. I have got acceptable results with a 300mm lens on APS-C with a shutter as low as 1/60th sec but I wouldn't recommend that unless you are desperate. The success rate drops a lot below say 1/250th. It's not just camera movement but also subject movement that is the problem at slow speeds.

QuoteOriginally posted by kayasaman Quote
What do you suggest I do in PP to bring the fox out more?In RawTherapee I already used AutoLevels, Saturation, Sharpening, Local Contrast, and Vibrance.... anything else I was a little afraid might add extra noise and damage the image quality.
Sorry I didn't realise you had already processed it. I can't speak about RawTherapee - I use DxO Photolab. I generally lower the microcontrast and leave clarity at 0 for the image as a whole and darken the image overall a little. Then I mask the subject for local adjustment and increase the levels a bit, increase microcontrast and add clarity to the subject. This makes it stand out a bit. It needs a light touch though, so it doesn't look artificial. PL applies a little sharpening automatically and I usually don't add any. I find that microcontrast, exposure and contrast are usually better ways to increase perceived sharpness without artefacts. At a high ISO (say 1600 or higher) I use DxO's DeepPrime (AI) noise reduction, which is really good. I would also crop this image to about one-third of its current size.

Here a very rough edit of the jpg to indicate what I mean.


I think the white balance is a little off too. The leaves are too yellowish and there is a magenta cast. With a RAW image I would address this first, metering from the white or grey fur or the grey metal on the roof
04-28-2022, 07:04 PM   #36
Senior Member




Join Date: Jun 2021
Photos: Albums
Posts: 148
Original Poster
QuoteOriginally posted by Des Quote
That's not surprising. I have got acceptable results with a 300mm lens on APS-C with a shutter as low as 1/60th sec but I wouldn't recommend that unless you are desperate. The success rate drops a lot below say 1/250th. It's not just camera movement but also subject movement that is the problem at slow speeds.


Sorry I didn't realise you had already processed it. I can't speak about RawTherapee - I use DxO Photolab. I generally lower the microcontrast and leave clarity at 0 for the image as a whole and darken the image overall a little. Then I mask the subject for local adjustment and increase the levels a bit, increase microcontrast and add clarity to the subject. This makes it stand out a bit. It needs a light touch though, so it doesn't look artificial. PL applies a little sharpening automatically and I usually don't add any. I find that microcontrast, exposure and contrast are usually better ways to increase perceived sharpness without artefacts. At a high ISO (say 1600 or higher) I use DxO's DeepPrime (AI) noise reduction, which is really good. I would also crop this image to about one-third of its current size.

Here a very rough edit of the jpg to indicate what I mean.


I think the white balance is a little off too. The leaves are too yellowish and there is a magenta cast. With a RAW image I would address this first, metering from the white or grey fur or the grey metal on the roof

The white balance may have been because I upped the saturation a little.

Thank you so much for all the tips, they will definitely be very useful on subjects like this. I don't know if RT does masking but I have GIMP which can do it though I need to understand more about the adjustments.

I will relook at RAW file and see how I can tweak it per your example.
04-29-2022, 04:29 PM - 1 Like   #37
Des
Loyal Site Supporter
Loyal Site Supporter
Des's Avatar

Join Date: Jan 2014
Location: Sth Gippsland Victoria Australia
Photos: Albums
Posts: 5,772
QuoteOriginally posted by kayasaman Quote
The white balance may have been because I upped the saturation a little.
No I think it's more likely the setting in the image.
QuoteOriginally posted by kayasaman Quote
I will relook at RAW file and see how I can tweak it per your example.
I'm sure everyone has a different way to do it. For some images it won't matter whether the changes you make apply to the image as a whole, rather than just the subject. But where, as here, there are a number of other elements in the image, it can help to emphasise the subject and de-emphasise the other elements. For wildlife images, I find the ability to make local adjustments invaluable. I've never used RawTherapee, but it seems to have this capacity too: Local Adjustments - RawPedia

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!
birds, button, data, dslr, dust, exif, focus, frame, full frame, full-frame, images, iso, issues, k-1, k-1 ii, k1, lens, mark, mode, pentax k-1, practice, sensor, shutter
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
AF or MF for Fast-Moving Objects? butangmucat Photographic Technique 12 08-21-2016 07:44 AM
Pentax K-7 shooting moving objects SkipperRi Photographic Technique 5 07-28-2013 12:37 AM
Using 55mm 1.4 to shoot moving objects? junototoro Pentax SLR Lens Discussion 14 09-10-2012 11:31 PM
So how do YOU handle focusing on moving objects? veezchick Troubleshooting and Beginner Help 19 12-20-2011 02:50 PM
How to calculate minimum shutter speed for moving objects? Alberts Troubleshooting and Beginner Help 12 11-14-2011 01:52 AM



All times are GMT -7. The time now is 08:13 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