Found some good flashes for studio macro

mawyatt · Post by **mawyatt** » Sat Aug 19, 2017 1:02 pm

And the Flashpoint Rapid 600 (Godox GT600 I think). Has pulse width display too!

1/1 600WS 1/190 or 5263us
1/2 300WS 1/938 or 1066us
1/4 150WS 1/2150 or 465us
1/8 75WS 1/3968 or 252us Most Speedlights at full output are 1/220 (4545us)
1/16 37.5 1/6288 or 159us
1/32 18.75 1/9950 or 100us This was the benchmark power level 18.75WS
1/64 9.375 1/14,492 or 69us
1/128 4.6875 1/19,606 or 51us

BTW this can go down to 1/28,984 or 35us in burst mode.

As you can see, and Beatsy mentioned, having more up front power allows you to dive deeper into the power back-off curve and get the benefit of quicker optical pulses.

Best,

Mike

mawyatt · Post by **mawyatt** » Sat Aug 19, 2017 1:29 pm

enricosavazzi wrote:The Godox AD200 is indeed an interesting flash intermediate between speedlights and studio strobes. If anyone is interested, my review is here:

http://savazzi.net/photography/godox_ad200.html

ES,

Very nice review. Recommended reading for anyone in macro.

I had mentioned some time ago about someone coming out with a Speedlight/strobe that used the 18650 battery, can't believe that this hasn't happened!! All we have is proprietary battery cases with 18650s inside!! Why not just 3 or 4 18650s used like AA cells??

You should review the AD600 also, I've used them ever since they first came out a couple years ago. These are just plane great strobes for all sorts of work, inside and out!!

Also the new Adorama/Godox SK300II you should review. This is a great studio strobe for our use, it's fast (1/800 -1/2000, full to 1/16), has a 2% spec output variation, 300WS, built-in RF trigger and control, S1/S2 optical trigger, Bowens mount, good electrical design & construction, and is inexpensive ($120USD). This has become my workhorse macro studio strobe.

Best,

Mike

enricosavazzi · Post by **enricosavazzi** » Sun Aug 20, 2017 4:23 am

Incidentally, the AD200 also has a similar flash-length display in manual mode. I don't know whether it reads the values from a table of settings or it displays the actual flash duration, more likely the former.

mawyatt · Post by **mawyatt** » Sun Aug 20, 2017 5:22 am

Since it displays before the flash is taken it must be from a table.

Best,

Mike

concon · Post by **concon** » Mon Oct 02, 2017 10:50 am

Reviving this topic as I recently purchased a Flashpoint Rapid 600 (no more batteries).

I ran a few tests yesterday and processed a few images. Everything is looking great! I'll need to create a setup for my rig to support the strobe above my lens/subject (my setup only allows it on one side of the table which is not great).

My biggest question is speed/stress. I know what its recycling time is (based on the specs), but is there any sort of buffer? (e.g. it'll recycle at what's listed in the spec up until a certain number of images .)

I experienced this buffer with my speedlights (they could be used at around ~1/4 power for a good ~100+ shots with a ~1.4 second delay). In my tests I took my strobe up to 1/16+9 with a 1.2 second delay/settle. What do you all think would be a safe minimum delay with this strobe? I tested down to an 80x and don't think I'll need to go above 1/8 (will be less once I build out that addition).

mawyatt · Post by **mawyatt** » Mon Oct 02, 2017 12:59 pm

As mentioned by someone before, don't rely on the Speedlight or Strobe indicators to represent a full charge, these represent something less than full charge, so allow much longer to ensure the capacitors have reached full charge.

I usually allow 5 seconds or longer between flashes for other reasons like vibration settling and in-camera TIFF file write time. The AC powered strobes I have charge much faster than the battery powered ones, which helps as well as not dealing with batteries!
Concon,

Your Flashpoint 600 is probably one of the fastest refreshing strobes around, so a couple seconds at 1/8 output I would think should be fine.

You can run a simple experiment. Just shoot a blank white paper like it was a stacking session and vary the time between exposures. Then take a look at the files for any exposure variation, this should provide a clue about how quickly the strobe is recharging and how uniform the output is.

BTW the Flashpoint Rapid 600 is a really good strobe with very fast output optical flash, and very fast refresh time. It's also nice to have the constant color mode available. These are very heavy though and a C Stand is a good means to mount them and allow some position flexibility.

Best,

Mike

concon · Post by **concon** » Mon Oct 02, 2017 3:14 pm

Thanks for the reply, as always

I swapped to hi-jpg shooting for my stacks a few months ago to increase speed- there's only been a few instances where shadows were not recoverable (I can definitely see needing a longer refresh/settle if shooting RAW another lossless format).

I grabbed the flashpoint based on your recommendations here in the forum; I trust your experience!

I was anticipating grabbing and trying a Manfrotto Double Articulated Arm as it's rated up to 11lbs and reviews say it's extremely reliable when used at it's standard rating (I was also going to clamp it to an additional 8020 support the arm does give).

mawyatt · Post by **mawyatt** » Mon Oct 02, 2017 4:24 pm

Concon,

Thanks, glad you like it:D

Run the experiment I mentioned, but use the RAW output (think it might give better exposure variation results). This should let you know how quick the Rapid 600 can refresh. If you do, please inform us of the results.

Adorama has a nice C Stand which is very well built.
https://www.adorama.com/Als.Mvc/nspc/Pr ... /True/True

These are what I use, especially for heavy objects, and your Rapid 600 certainly isn't light!!

I guess if you are using in-camera (lens) focus stacking then moving vibration isn't a problem and you can speed things up considerably.

Since the Rapid 600 has a Bowens mount you can get all sorts of light modifiers off eBay. One that might be useful is a snoot which helps direct light to a tighter location, these are about $15 on eBay and work fine.

Best,

Mike

concon · Post by **concon** » Mon Oct 02, 2017 4:54 pm

Excellent,

I'll definitely run that and be sure to post once I do. I'm crunched on time lately so it'll be a bit...I'm still trying to get my new rail up and running

I'm very interested in the snoot and will take a look at the other accessories as I have a few things in mind already.

Vibration definitely isn't something I've had to deal with recently. I built a very secure rig and the rail vibration doesn't last but half a second after movement (I went through plenty of pains to get here though).

I was looking at some of those C stands, but they all seems quite heavy and don't look like they'd be much fun to lug around. I shoot for clients often so I love portability, but definitely know that I shouldn't risk a strobe falling on my lens/tubes- ha!

mawyatt · Post by **mawyatt** » Mon Oct 02, 2017 7:13 pm

Watch out for the lens camera assembly, this can have a very long dampening period and take considerably longer to die out than the stiff rail base. The camera can induce significant vibration with the mirror and shutters, and even on a stiff base will "ring" for a long time. Sometimes lens braces help, especially if they are the lenses & extension tubes with long lengths to support objectives and tube lenses.

Yes the C Stands are heavy.

Solution, get an assistant to carry them

Best,

Mike

concon · Post by **concon** » Mon Oct 02, 2017 7:47 pm

When you refer to a camera lens assembly, what exactly do you mean? I have an idea but want verify.

I'm using a Raynox as my relay with extension tubes. My camera has a silent shooting setting, but it's not enabled (forget why) so I definitely see the vibrations from the shutter- you're dead on about that. I could use a more thought out brace for my tubes. I've fashioned one with good support, but it could always be better.

An assistant... One day!

mawyatt · Post by **mawyatt** » Tue Oct 03, 2017 5:52 am

With the Raynox you will need 125 or 208mm total extension from sensor to the Raynox flange, then the objective sits out in front even further from the camera mount. This arrangement can produce almost 200mm of lens assembly hanging off the camera flange. This alone is not very stable and will "ring" even with the best camera adapter (the thin Nikon F adapters are very flexible, the thicker BR2A is better but still flexes). So some lens support is required.

Hejnar Photo has an adapter for telephoto lenses that works. It's a long ARCA rail with a vertical sector thats screws on the end. The vertical section is a "Y" shape with 2 tiny wheels that engage the lens (allows rotation). The lens end sits in the "Y".

Wemacro has a support for long lens used in macro work, it's a large ring with nylon screws to hold the lens in place. The ring base is screwed onto the rail.

Both cases the attaching fixture must move with the focus rail.

concon · Post by **concon** » Tue Oct 03, 2017 11:21 am

Yup yup! My tubes are at the right length (as far as my testing has determined).

The support I'm using now is similar. It's an old flat manual focus rail that I've mangled into a new use (camera on end with a support for my tubes on the other- works well as a DIY, but will most likely just 3d print something more so the objective is also supported). I'll take a look at the other products you listed for ideas.

Andy Davies · Post by **Andy Davies** » Sat Oct 07, 2017 5:29 am

I guess there might be an optimum flash power and length of flash pulse.

The greater the number of photons arriving at the subject per second may induce subject movement as discussed in this thread http://www.photomacrography.net/forum/v ... s&start=15

Conversely, a fast enough flash burst time is required to eliminate subject movement due to vibration of the rig, air movement etc.

mawyatt · Post by **mawyatt** » Sat Oct 07, 2017 6:27 am

Andy,

You might be able to predict this "optimum" pulse width mathematically, would be an interesting topic for a PhD student in Thermodynamics. My intuition tells me this will be a low Q optimum though.

Best,

Mike