TTL vs Manual Flash Explained | Mark Wallace | Exploring Photography 

Incredible work Mark. Been watching you for years. You have helped me so much. Thank you

Reminds me of good old days, 10+ years back, purchased all your training videos, speedlights in studio, on location lighting, and many more. I still have all of them and review now and then. Also followed all your Adorama free videos and loved all of them. You are just wonderful, Mark! One of those born-to-be-teacher persons.

Mark, that’s the best explanation I ever heard yet. Thank you, sir.

I can't help but to learn each and every time I watch one of your videos. This was so good for me that I can't wait to work with this in my garage. (Very amateur person here). Thanks

Mark, always great content and thanks for explaining in great detail

Very good lesson on studio flash. Really appreciate it.

I learned to use flash assisting Monte Zucker who introduced dual flash photography to wedding photography back in the late 1960s when wedding shooters switched from B&W to color and realized they couldn’t expose the white dress and black suits with detail in sunlight outdoor or single flash indoors. Monte used one flash on a bracket mounted directly above his TLR Rolleiflex as centered “neutral” fill and mounted an identical power flash on a modifed IV pole which could be wheeled around with one hand. My training started with tending the off camera flash and moving it relative to where the nose of the subjects were pointing, keeping it 45° from the noses for the same 3D modeling on the faces was natural lighting at midday when the sun is at that angle. Exposure and ratio were controlled by distance. At 11ft camera / fill distance the off camera flash was placed at 8ft which made it 2x (one stop) brighter, the ratio needed to record a full range of detail from black to white on color negative / print. The aperture based on testing (looking at the shadow exposure) was f/8. If moving in to 8ft for a tighter crop moving the off camera flash to 5.6 feet to keep the ratio the same and the aperture was closed to f/11 to keep the exposure the same. Moving into 5.6ft for a close up of the table setting or flowers the off camera flash moved to 4ft and the aperture changed to f/16.. You will note the coincidence between the distances we shot at and f/stop numbers. Changing distance from a light source from 1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32 feet or meters will change the intensity of the light source by one f/stop per the inverse-square law. Shooting from 11, 8 and 5.6 feet (judged by eye and paces) with off camera flash at 8, 5.6 and 4 feet respectively, covered 90% of the photos taken offering very consistent control over the lighting and ratio and giving the flash lit photos 3D realism single flash shots can match even when the light is bounced. I still use the same Fill on bracket, off camera flash on rolling stan with my Canon flash both in manual mode for static set-ups like shooting head shots of dozens of people for a church directory and ETTL-II for ‘run and gun’ PJ style photos. When shooting manual portraits I set lights by draping white and black hand towels I carry in my bag over a light stand, set aperture to f.8, raise the Group A fill on camera until I can see detail in the black towel with it’s histogram spike falling inside the left edge of the histogram then adjust the Group B off camera camera flash until the white towel is barely triggering the clipping warning in the JPG playback when shooting RAW or is 1/3 stop below clipping if shooting JPEG. Once set to record detail from black-to-white on my camera sensor range any subject with any clothing or skin color will be accurately rendered with flattering 3D modeling without and adjustment of lighting between subjects which would be necessary if using ETTL exposure which will react and change flash power based in the light reflected from clothing and skin tone. I know from static testing with the white and black towels in ETTL mode that a A:B (Fill:Key) ratio of 1:2 will render a full range of detail so when shooting ETTL I leave the ratio at 2:1 and just adjust the flash power based on the clipping warning in white highlights - keeping them below clipping - by monitoring playback as I shoot and adjusting FEC as needed.

Great job and clear explanation!

You have to watch the video again to get great tips. Many thanks for a great video.

Hi, Mark. In the last part of the video, when you switch from TTL to manual flash, the amount of light that comes out of the soft box remains the same but Destiny gets more light when she's on the white background because she's closer to the light source. This is just to be fussy and apart from that, I find your video very useful.

Always the best teacher!

thank you so much for explaining!

RE SUPER CLASS!!!!! MUCHAS GRACIAS SALUDOS DESDE PERU!!

Great video as usual.

A master teacher. Hope to see a course on lightbox or product photography for home if you have the time. Thanks for having the ttl class.

Always great to see that you are still giving instructions in your short, upbeat Mark Wallace style. I use a trick that you taught several years ago when I'm using my Canon on-camera flash for portraits (amateur at best). You suggested using E-TTL II meter....Eval (FacePrty). That has been very helpful. What part of the world are you exploring at the present time?

Excellent tutorial

Your discussion of TTL-mode flashing once for metering and again for exposure reminded me of why TTL can be a problem with live insect macro photography. That pre-flash may scare away fast-reacting insects before the 2nd flash has time to fire 🙂.

How about review on your vintage cameras that you used in the past? Great work as always. Enjoyed the videos in retirement.

Muchas gracias.

An Amazing Video, thanks Mark! 👌👌👌 🤝🙏 🇿🇦

Thank You for the video, that was refresher for me when I was I was in photography college.

Well Done!

Great video as usual, Mark but you forgot to mention one more solution for TTL that is face exposure priority. I know you have said that not all cameras have this function but all mirrorless cameras nowaday have the face detection AF so I wonder if it works the same as face exposure priority function on your Canon? If it possible, please make a video to compare between cameras. Thanks very much.

Hi Mark, I have been watching your videos on TTL and I have been experimenting with different TTL settings. When I use TTL flash compensation on my Godox AD100 AND AD200, I see almost no light change between 0 and -3. When I try the same experiment on my AD300, there is significant difference between -3, 0, and +3. To make things even weirder, my AD200 that has almost no difference between -3 and 0 behaves differently when i put the bulb head on it. Then, it behaves just like my AD300 and has distinct light level changes with all 3 variation. Help! I don't know why this is happening.

TTYL, TTL!

So Should i get TT600 without TTL and save some bucks or get TT685 with TTL Flash is that usefull?

All these TTL & Manual Flash tutorials and not a mention of the flash exposure rectangle, and how it's linked to the camera metering à la exposure triangle.