infestation Loc: Brampton, Cumbria, UK

Seeing as it a typical UK winter very wet and no bug life I have been playing with the diffuser again, this time trying out the concave but wasn't too impressed with the results thus far, I have reduced/increased the curvature bit by bit,, but was still getting hot spots , so took a shot of the reflection, this shows the hotter area in the center, how did you get around this? Double up the material nearer the head?

At the minute I just seem to be better with the straight edge, I am still trying to persevere with the idea maybe just need to go LARGE?

concave showing hotter area

Nikonian72 Loc: Chico CA

I am using a conventional, commercial 6x8-inch softbox diffuser. Hotspots are a universal macro speedlight problem, so resolutions can be easily adapted to different diffuser builds.

My FotoDiox has an internal white cloth strip that I can stretch from one side to the other. Used in conjunction with my speedlight set to WIDEST coverage, and the speedlight drop-down plastic diffuser in place, I am quite pleased with my corner-to-corner diffusion. Emulating the additional internal diffuser may spread more light to your corners, especially with a curved diffuser face.

LoneRangeFinder Loc: Left field

There is a benefit to size. (yes, size matters!). I have built more DIY softboxes than I should admit. I ended up shelving most of them and using a conventional "store bought" diffuser much like the one Douglas uses. I did this because I work in the rain. and the paper doesn't hold up.

If you have a drop-down diffuser on the flash head this can often diffuse the light.

martinfisherphoto Loc: Lake Placid Florida

Whats the size, dimensions? My go to softbox is 9inches by 7inches at the diffused end. This diffused end is about 6 inches away from the flash, once the flash is pushed into/seated/ in the diffuser. If your going to use paper towels, use the Good quality ones, bounty, good thick ones, they diffuse the light better. You can also use thin plastic over the paper towel to protect from the weather. I can go for months with no protection on my paper towel, but easy to replace. In fact I would recommend replacing after several months as fine dirt and dust will block your flash. The best Even, no hotspots would be styrene, like coffee cups and throw away paper plates. The best for color is Tissue paper, but you will have slight hotspots. This will not affect your shots unless you dealing with dew drops or spider eyes for instance. Don't worry about the small stuff, start shooting and building the softbox that works best for you and your subjects. The larger the box the better the light. If you want the best possible light you have to build your own, if you want light that will work use the store bought versions. Sorry Guys..

A-PeeR Loc: Houston, Texas

Yes, what are the dimensions of the diffuser? What flash are you using with the diffuser? For my 600RT-EX the diffuser 19cm across, 21cm deep, top of diffuser face is 7.5cm at the apex of the arch and width of the arch is 6cm deep. I have a sleeve on top of the diffuser that supports that spaces the flash head so the face of the flash is flush with the top of the diffuser. This separates the face 6cm from the diffuser. Like Allen, I employ the built in Frenzel diffuser and like Douglass set the flash to it's widest coverage. I get excellent illumination coverage from edge-to-edge. You can see a picture of a very similar one I made for a 430EX II flash on the Macro Equipment Set-Ups thread. It's the last entry on page 5.

infestation Loc: Brampton, Cumbria, UK

The flash is the Yongnuo 560 II, the diffuser is 7-1/2" x 5-1/2" with the concave arch on this 1-3/4", just under 4" from the face of the flash, the flash has the built in dropped and likewise widest setting, this out of the trials so far had the least trouble with the hot spots, but pretty much the lowest curvature, I have been after making a good portable set up, and was liking the lighter material on the bracket, to be fair have been struggling to better the original box just it is deceptively heavy and has a tendency to move the flash breaking the trigger contact, thus trying out the different styles.

Thanks for the experiences so far, look like I will be upsizing :)

LoneRangeFinder Loc: Left field

I have this same model Yongnuo. Here is what I do: I have my flash (as others have mentioned @ the widest angle setting with the drop down panel) and I have added an additional sheet of paper towel inside the diffuser (Bounty is the best!).

It's not concave-- and the diffusion may seem like "overkill" but I don't think so. I am still often shooting at 1/32 to 1/64 speedlight power on Manual. I do agree that bigger is better-- I've just chosen portability for most field work. (One of my softboxes is 8x10. If you look at Shahan's videos, his is about this size.)

My other rig is an R1C1 with two flash units + a DIY diffuser which is way better than Nikon's snap-on units. I already have four "models". ;-) 8-)

martinfisherphoto Loc: Lake Placid Florida

My first were built from good cardboard stock, supper light and durable. A little duct tape makes them super strong. I now use 3/16 inch thick foam board, which you can find at any craft store. Even stronger, easy to cut, already bright white, no need for aluminum foil on the inside. If your mounting your flash on the camera hot shoe I would get it out there a little further. I'll try and post a photo of softbox I'm using now, later today.

LoneRangeFinder Loc: Left field

Foam core is brilliant. I never cared for foil-- but neither will I ever argue with the bottom line which is the result. I had begun to use white matte spray paint on my DIYs.

martinfisherphoto Loc: Lake Placid Florida

Here's a look at my diffuser, not concave but still from the hotshoe and not side mounted. I built the diffuser angled down to get closer to the subject and also to turn the flash power down. Works great from the hotshoe. I've also switched to Viva paper towels. They are built more solid/no dimples/and even in diffusion. Hope this helps.

dar_clicks Loc: Utah

PayLess Fabrics has some rip-stop nylon that works pretty well in a DIY diffuser. Available by the yard -- Amazon.