Random Photography Stuff

[RobDickinson]

I must be feeling off nothing I want to buy at the moment.

Well I wouldnt mind an 11-24 or an a7r2 or a 17tse but really I can live happily without them. Oh mebe another good tripod..

[RobDickinson]

I do need another bag though my lowepro is falling apart

[LongQ]

DibblyDobbler said:

Ps - when are you up here again? Soon isn't it?

The Week after next. Logistics still a little bit of a grey area but I'm working on finding out what the likely plans are.

Of course my thoughts have, obviously, been addressing possible photographic opportunities and I have a shopping list of bits and pieces that might be useful to aid the creative attempts whilst "on location".

The trouble is every time the internet serves up a new web page I see something else that seems to be "vital" for the trip.

Rob just mentioned that strange word "need" , which was a little upsetting I have to say. However my list does seems to include a few things (well, most actually) that would not be vital at all and I suspect that the rest might be "vital" but only if certain opportunities arise. Which they probably wont.

[DibblyDobbler]

RobDickinson said:

I must be feeling off nothing I want to buy at the moment.

Well I wouldnt mind an 11-24 or an a7r2 or a 17tse but really I can live happily without them. Oh mebe another good tripod..

I'd like to see what you could do with the 11-24 Rob - it looks like a beast!

[DibblyDobbler]

LongQ said:

The Week after next. Logistics still a little bit of a grey area but I'm working on finding out what the likely plans are.

Of course my thoughts have, obviously, been addressing possible photographic opportunities and I have a shopping list of bits and pieces that might be useful to aid the creative attempts whilst "on location".

Well let me know if you fancy a bridge one evening

[RobDickinson]

DibblyDobbler said:

I'd like to see what you could do with the 11-24 Rob - it looks like a beast!

I've been trying to justify not owning one for a long time, every review makes it harder..

[LongQ]

RobDickinson said:

DibblyDobbler said:

I'd like to see what you could do with the 11-24 Rob - it looks like a beast!

I've been trying to justify not owning one for a long time, every review makes it harder..

??


Have I accidentally landed on the inverted logic PH forum this morning?

[RobDickinson]

Its $4500 here , for that I can stitch 2 images and buy a lot of beer

[LongQ]

RobDickinson said:

Its $4500 here , for that I can stitch 2 images and buy a lot of beer

Well yes, but ......


Think of the time saving (and therefore cost reduction based on the value of one of your hours) when not having to mess around with stitching requirements!

However, throwing the "buy a lot of beer" argument into the equation is more PH like thus causing some confusion in the man logic sub-section of my internal analysis engine.

Challenges, challenges.

[Mr Will]

DibblyDobbler said:

Help Please

I have been fannying about experimenting with my popup flash to see if I can get it to work for macro shooting.

Normally I'm on Manual mode + f14 + 1/200 + iso100 ish or something similar.

The flash is not that powerful (as you would expect) so I though to myself to whack the Flash exposure compensation up to max (ie +2) - but I'm not understanding what it does!

With all other settings the same - for a middling aperture(eg f9) - the FEC does make it brighter or duller

But for a small aperture (f16) it has no affect at all - is this because the flash is already at maximum power and the dilithium crystals will no take it Captain ?

TIA

Thought I'd chip in on this one since it never got answered.

Starting with the basics; even if you are in manual mode your flash will still be automatic - the camera will turn it's power up or down to achieve the "correct" exposure. Flash Exposure Compensation allows you to turn the exposure up and down relative to the camera's notion of "correct" in the same way that regular exposure compensation works in Av/Tv mode. You shouldn't need to mess with it just because you are changing other settings.

The other settings can make a difference to the amount of flash power required though. Aperture and ISO both affect the flash in the same way that they affect any other light. The big difference is that the shutter speed does not affect the flash exposure. This allows you to adjust the balance between the flash and ambient lighting by using a longer or shorter shutter speed.

The final factor is distance. Light is subject to the inverse square law and loses half it's power every time you double the distance. This is why bouncing flash requires a much more powerful light - taking the long way round greatly reduces it's effectiveness.

Now why isn't your flash making a difference at f16? You were correct in your assumption that your flash is hitting maximum power and has no more to give. The subject is close, which is giving you an advantage but it's not enough to overcome the tiny aperture. If you don't want to open the aperture (and don't want to buy a bigger flash!) then your options are limited. Extending the shutter duration will allow in more ambient, but that will likely make little difference compared to the extremely bright flash. You can't move closer, you can't turn the flash up any more and so that just leaves the ISO. Moving from ISO100 to 200 will double the effectiveness of the flash, reducing the power required from 120% to 60% (for example). Going to 400 would drop that to 30%.

Apologies for a slightly rambling explanation, but I hope that sheds some light on how it works

[DibblyDobbler]

Mr Will said:

Thought I'd chip in on this one since it never got answered.

Starting with the basics; even if you are in manual mode your flash will still be automatic - the camera will turn it's power up or down to achieve the "correct" exposure. Flash Exposure Compensation allows you to turn the exposure up and down relative to the camera's notion of "correct" in the same way that regular exposure compensation works in Av/Tv mode. You shouldn't need to mess with it just because you are changing other settings.

The other settings can make a difference to the amount of flash power required though. Aperture and ISO both affect the flash in the same way that they affect any other light. The big difference is that the shutter speed does not affect the flash exposure. This allows you to adjust the balance between the flash and ambient lighting by using a longer or shorter shutter speed.

The final factor is distance. Light is subject to the inverse square law and loses half it's power every time you double the distance. This is why bouncing flash requires a much more powerful light - taking the long way round greatly reduces it's effectiveness.

Now why isn't your flash making a difference at f16? You were correct in your assumption that your flash is hitting maximum power and has no more to give. The subject is close, which is giving you an advantage but it's not enough to overcome the tiny aperture. If you don't want to open the aperture (and don't want to buy a bigger flash!) then your options are limited. Extending the shutter duration will allow in more ambient, but that will likely make little difference compared to the extremely bright flash. You can't move closer, you can't turn the flash up any more and so that just leaves the ISO. Moving from ISO100 to 200 will double the effectiveness of the flash, reducing the power required from 120% to 60% (for example). Going to 400 would drop that to 30%.

Apologies for a slightly rambling explanation, but I hope that sheds some light on how it works

Excellent - Thankyou very much!

I am only just now beginning to realise how much I don't know - how the flash works is a particularly grey area. One other thing you might know - for macro I have a MT24-ex twin flash. Quite a fancy thing but I just use it on Manual (camera on manual also: 1/200 + f14 ish). Somebody was saying that if I fire the flash at 1/2 power or 1/4 or 1/8 etc I am increasing the effective shutter speed as the flash is firing for a shorter duration as I dial back the power. Does that seem right? Thanks

[LongQ]

DibblyDobbler said:

.... how the flash works is a particularly grey area.

Then you need something with more power.

[Mr Will]

DibblyDobbler said:

Excellent - Thankyou very much!

I am only just now beginning to realise how much I don't know - how the flash works is a particularly grey area. One other thing you might know - for macro I have a MT24-ex twin flash. Quite a fancy thing but I just use it on Manual (camera on manual also: 1/200 + f14 ish). Somebody was saying that if I fire the flash at 1/2 power or 1/4 or 1/8 etc I am increasing the effective shutter speed as the flash is firing for a shorter duration as I dial back the power. Does that seem right? Thanks

That is correct BUT the flash duration will be very short even on full power. 1/1000 of a second would be pretty typical. Unless you are trying to freeze a hummingbird in flight you probably don't need to worry about it.

[DibblyDobbler]

Mr Will said:

That is correct BUT the flash duration will be very short even on full power. 1/1000 of a second would be pretty typical. Unless you are trying to freeze a hummingbird in flight you probably don't need to worry about it.

Thanks again Mr Will - appreciate the sensible replies. (LQ - 15 minutes on the naughty step!)

[LongQ]

DibblyDobbler said:

Mr Will said:

That is correct BUT the flash duration will be very short even on full power. 1/1000 of a second would be pretty typical. Unless you are trying to freeze a hummingbird in flight you probably don't need to worry about it.

Thanks again Mr Will - appreciate the sensible replies. (LQ - 15 minutes on the naughty step!)

Naughty Step?


Very 20th century as I understand things.

Truly the use of flash in an environment outside a "studio" setting is diving into the realms of black magic - despite the attempts of some remarkable practitioners to suggest otherwise. A certain type of brain is required.

eTTL, or anything related to it appears to be the work of the devil - and then some.

Manual is cool - but in the macro mpe universe is pretty much self contained since the available light aspect of the shot will mostly be somewhat compromised. Right?

That may be intentional. Or it may be as claimed - just physics.

[Simpo Two]

DibblyDobbler said:

Thanks again Mr Will - appreciate the sensible replies. (LQ - 15 minutes on the naughty step!)

If you want to try flash photography seriously, get an external Speedlight. You'll have much more power, the ability to operate it manually, off-camera flash, strobe... I was photographing an orchid in a wood a few days ago and used the modelling light function - just enough to cheer up the subject without turning it into a white stick. If you fancy a Nikon SB-800 let me know.

[DibblyDobbler]

Simpo Two said:

If you want to try flash photography seriously, get an external Speedlight. You'll have much more power, the ability to operate it manually, off-camera flash, strobe... I was photographing an orchid in a wood a few days ago and used the modelling light function - just enough to cheer up the subject without turning it into a white stick. If you fancy a Nikon SB-800 let me know.

Thanks Simpo - I will do some digging...

[LongQ]

Simpo Two said:

DibblyDobbler said:

Thanks again Mr Will - appreciate the sensible replies. (LQ - 15 minutes on the naughty step!)

If you want to try flash photography seriously, get an external Speedlight. You'll have much more power, the ability to operate it manually, off-camera flash, strobe... I was photographing an orchid in a wood a few days ago and used the modelling light function - just enough to cheer up the subject without turning it into a white stick. If you fancy a Nikon SB-800 let me know.

Now now Mr. Simpo. Tempting Mr. DD into an entire system change in order to experience the joys of flash photography may break the rules of engagement for the thread.

[Simpo Two]

LongQ said:

Now now Mr. Simpo. Tempting Mr. DD into an entire system change in order to experience the joys of flash photography may break the rules of engagement for the thread.

Ah, it never occurred to me he might not use Nikon

[DibblyDobbler]

Simpo Two said:

LongQ said:

Now now Mr. Simpo. Tempting Mr. DD into an entire system change in order to experience the joys of flash photography may break the rules of engagement for the thread.

Ah, it never occurred to me he might not use Nikon

Actually I believe the Nikon SB-800 would work on a Canon Body so not so daft