Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-11-2018, 09:30 PM - 1 Like   #16
Site Supporter
Site Supporter
Alex645's Avatar

Join Date: May 2015
Location: Kaneohe, HI
Photos: Albums
Posts: 2,391
QuoteOriginally posted by Skodadriver Quote
I have recently purchased a used Sigma EF-610DGST flash thinking I could use it during the grey days of winter in my back garden.
I chose ISO 400 to give me plenty of range with the flash and have assumed that longer exposures would leave me with mostly just the illuminated image as provided by the light from the flash.
Your Sigma is a relatively powerful flash, but there are still limitations with distance, ambient lighting, and subject speed.

The sync speed has nothing to do with what youʻre trying to accomplish. The main idea is that the flash itself would overpower the ambient light, and freeze everything it exposes. However, the flash duration is longer at full power vs. half power, for example. And if there is too much ambient lighting, it will contribute to ghost blurring.

Depending on the dynamic range of your sensor, youʻll want at least a 4EV difference between the flash exposure and the ambient lighting. That way, the flash will freeze any movement, and everything else will be relatively dark.

The flash duration of your Sigma at full power is 1/700". So full power would probably only freeze a flapping bird wing with a 50mm macro lens. So with a 300mm lens, youʻre going to want an effective shutter speed around 1/2500". With your flash, you should be getting 1/2800" flash duration at 1/4 power. But at that power, you need to be closer and to have less ambient light. Using a higher ISO, perhaps 1200, will help, but again the key is having a bigger difference between the ambient light and the flash exposure.

Note that many of the excellent examples posted are of birds perched and not moving. The flash brought out excellent detail, color, and eliminated camera shake, but not bird movement.


Last edited by Alex645; 01-12-2018 at 01:53 AM.
01-11-2018, 10:54 PM   #17
Site Supporter
Site Supporter




Join Date: May 2015
Location: Hampshire
Photos: Gallery | Albums
Posts: 827
Original Poster
My ignorance of much of the flash photography basics shows in the assumptions I make, this old dog needs to learn!
01-11-2018, 11:29 PM - 1 Like   #18
Site Supporter
Site Supporter
Alex645's Avatar

Join Date: May 2015
Location: Kaneohe, HI
Photos: Albums
Posts: 2,391
QuoteOriginally posted by Skodadriver Quote
My ignorance of much of the flash photography basics shows in the assumptions I make, this old dog needs to learn!
Honestly, what youʻre trying to do is more advanced than basics. Fill flash is commonly used by pros, but takes experience to understand what is not enough to fill shadows and what is too much and looks artificial.

On Tuesday this week, I was on a photo field trip with my students when suddenly the beach was invaded by swimsuit models, a photographer, and the whole support staff for Sports Illustratedʻs Swimsuit edition. They arrived around 1:00 pm and I know the top shots were going to happen around sunset about 4.5 hours later. Youʻd think it was fun and games, but all I saw were a bunch of professionals working hard to get specific results.

The next day Iʻm 4000 feet on the summit bog of Mt. Kaʻala with students, some trying to shoot rare birds. Of 24 students, one was a hard core birder and he was the only one with anything other than a dot or a blur. Shooting birds takes above average skill and patience, so all I can say is with perseverance, youʻll see improvement. My main suggestion would be to shoot when the ambient light is even darker so that your dominant exposure is from the flash. To understand whatʻs happening, try manual power settings for full control of the flash duration. P-TTL adds automation, and thus removes you from easier understanding of what is actually happening.
01-12-2018, 01:13 AM   #19
Site Supporter
Site Supporter




Join Date: May 2015
Location: Hampshire
Photos: Gallery | Albums
Posts: 827
Original Poster
QuoteOriginally posted by Alex645 Quote
Honestly, what youʻre trying to do is more advanced than basics. Fill flash is commonly used by pros, but takes experience to understand what is not enough to fill shadows and what is too much and looks artificial.

On Tuesday this week, I was on a photo field trip with my students when suddenly the beach was invaded by swimsuit models, a photographer, and the whole support staff for Sports Illustratedʻs Swimsuit edition. They arrived around 1:00 pm and I know the top shots were going to happen around sunset about 4.5 hours later. Youʻd think it was fun and games, but all I saw were a bunch of professionals working hard to get specific results.

The next day Iʻm 4000 feet on the summit bog of Mt. Kaʻala with students, some trying to shoot rare birds. Of 24 students, one was a hard core birder and he was the only one with anything other than a dot or a blur. Shooting birds takes above average skill and patience, so all I can say is with perseverance, youʻll see improvement. My main suggestion would be to shoot when the ambient light is even darker so that your dominant exposure is from the flash. To understand whatʻs happening, try manual power settings for full control of the flash duration. P-TTL adds automation, and thus removes you from easier understanding of what is actually happening.


I shall work on shooting with less ambient light, manual flash and my patience. The birds in my back garden seem much warier this year, maybe the increase in neighbours cats using my place as a toilet and stalking ground has caused that.
Thank you for the pointers.

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!
ambient, background, camera, christmas, contribution, flash, image, iso, light, mode, pentax help, photography, scene, shutter, troubleshooting
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
to Flash or not to Flash for portraits? and a question blurb on lens preferance Fcsnt54 Pentax Medium Format 13 07-23-2017 08:36 PM
Pentax me super not focusing & its not the lens, please help :) jayjya027 Troubleshooting and Beginner Help 6 12-18-2016 03:58 AM
Cactus RF60 Wireless Flash With Wireless Flash Transceiver V6 Single - deal or not? micromacro Flashes, Lighting, and Studio 10 11-08-2016 11:19 PM
Not one, not two, not three, not four, but a wedding where half attendees are bob. LeDave Photographic Industry and Professionals 12 05-16-2016 03:40 AM
Resolution is not the same as IQ, not even close. normhead Pentax SLR Lens Discussion 54 04-10-2016 07:41 AM



All times are GMT -7. The time now is 11:39 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