Tutorial: Scaling Historical Sewing Patterns with Photoshop - Part 2 - Turn Your Bodice Sloper into a Photoshop file

In Part 1 I discussed what you'll need to follow along with my tutorial using my pattern drafting method that will ultimately show you how to take a vintage or historical sewing pattern and scale it in Photoshop and produce a pattern which will actually fit you.

Today I'm discussing How to take your personal Sloper and put it in Photoshop. This step is very important because it's the basis for any pattern you want to create, and you'll use it again and again.

Main items You will need:
* Camera/Phone (or a scanner if you have one, I don't)
* Sloper - Note: for demonstration purposes I'm just showing the front and back section, not the sleeves, so don't forget to include your sleeve when you do this yourself.
* A suitable background - see below 
* Graphics Program - Photoshop etc

Here's an overview of the points to consider when photographing your sloper.
1 - Keep the photo as true and square as possible, you don't want the shape distorted.
2 - know the exact measurements of your background,
3 - a high contrast image with crisp edges will be easier to manipulate later in Photoshop.

Let's begin:
Point 1) To keep the sloper true, and as free from distortion as you can allowing for the nature curve of a camera lens, you need to take a 'flat' photo. Hold the camera pointing down, completely level/parallel to the sloper and positioned over the middle of the sloper.

When you look at the screen make sure the edges of your background are the same distance all round, this helps makes sure everything is parallel.

This photo is angled, see how the edges of the cutting mat taper in from the edge of the photo. (click to see larger image)

This photo is as true as I can get it, the camera is held level and all the edges are parallel (click to see larger image)

Point 2) What Background to Use - Note: this is important. 
Photograph the sloper on a background that you know the exact measurements of, for example a large sheet of paper, or mark out a rectangle on the carpet with masking tape. Whatever you use ensure it has right angles and is slightly larger than the sloper.

An A2 cutting mat is a suitable background, and the back side of my sloper, covered in black interfacing creates a high contrast with clearly defined edges. (click to see larger image)

3) High Contrast - you want the edge of the sloper to be clearly definable, because ensuring this will make later Photoshopping steps easier. To have a nice crisp edge the easiest way is to make the sloper stand out from the background by having a colour difference between sloper and background.

My sloper is made from plain butchers paper and the dart edges are hard to see. However when the sloper was made I ironed on black interfacing to strengthen it, so by simply flipping the sloper over, I have a solid block of colour with clearly dined edges.

To follow points 2 & 3, I'm using my A2 size cutting board and a ruler, and because the A2 board can only fit one part of the sloper at a time, I take two photos, one of the sloper front, one of the sloper back:

Final photo: Bodice sloper Back (click to see larger image)
Final photo: Bodice Sloper Front (an edge was curling so I'm holding it down with a pin in a way which doesn't interfere with the background)
Disclaimer: You will see despite my care the photos aren't entirely true, so if you have a better way of creating a digital version of your sloper, for example access to a scanner, then use it.
Or if possible have your sloper drafted on the computer. (Just make sure you mock it up in fabric to test the fit.)

Right! Time to open the bodice slopers photos in our graphics program (remember to include your sleeve sloper also)

I'm going to start with the Bodice Back. Looking at my final photo I check the measurements on the cutting mat, although the mat is A2, I've lined the bodice in one corner, and used a ruler to help guide me. So I know in order to create a life-sized 1:1 scale copy of my sloper I need to start with a new Photoshop document at 49cm by 30cm.

Note: I'm working with full-sized patterns here, this makes for very large documents, but I could just as easily create a half-sized version by opening a document at 24.5cm by 15cm, and then I would just have to remember to scale it up before I printed it.
This just creates one more step and one more thing to remember, which is why I don't bother.

Start up Photoshop, open a New Document (Ctrl N), as pictured below and make it the size of your measured background, mine is 30cm by 49cm, and set the Resolution to 300 pixels per inch, which is print quality resolution. (After all at the end you want to be able to print a nice clear pattern.) Don't worry about the colour mode.
Set up your New Doc to the size precise of your background, and at 300dpi (click to see larger image)

The blank document opens and if your Rulers aren't on, turn them on (Ctrl R), or View>Rulers.

Turn on the Rulers (click to see larger image)
You'll need the Rulers set to the unit of measure that you used in the sloper photo. I placed my sloper on a metric cutting mat along with a metric wooden ruler, so I want my Photoshop rulers to also be in metric.

If your Photoshop Rulers are set to another unit of measure, hover the mouse over one of the Photoshop Rulers, indicated in the picture below by the red boxes. The cursor will change to a white arrow, right click the mouse and from the pop-up menu select the units you want. I set mine to centimetres.

Set the Rulers unit of measure (click to see larger image)

Now we need to open the actual photo of the bodice back, so (Ctrl O) or, File > Open and select your image. My photo was taken landscape format, but it's much easier to view patterns in portrait, so when my bodice photo is open I need to rotate it. Image > Image Rotation > 90 degrees clockwise

Rotate the original photo of your sloper to portrait (click to see larger image)

And now we want to take the photo of the sloper and put it into the set up 49 by 30 document.

Select the sloper photo, (Ctrl A), or Select > All. A dashed line will appear around the edge of the photo.
"Select All" the sloper photo (click to see larger image)

Copy the selected photo to the clipboard (Ctrl C), or 

Copy the Selected sloper photo (click to see larger image)

Return to the document you created at the specific background size by going to the Window menu and you'll see it down the bottom.

Return to the previously created blank document (click to see larger image)

 Now we'll paste the copied sloper photo onto the blank document (ctrl V) or Edit > Paste.

Paste the sloper photo into the blank document (click to see larger image)

The photo will appear as a new Layer in the document. If your Layers palette isn't open, to view the different Layers go to the Window menu and select Layers. (see below)

Open up the Layers Palette (click to see larger image)

Depending on the resolution your camera was set to, I think mine was only at 5megs, the sloper photo maybe smaller than we need it to be. So we're going to enlarge this layer, matching the measurements in the photo to the edges of the document, thereby creating a full sized 1:1 sloper document.

To enlarge to photo layer, we'll use free transform tool, (ctrl T), or Edit > Free Transform.
(Note: the Layer which the sloper photo is on must be the selected/active layer)
A frame will appear around the Sloper photo layer, as pictured below:

Select Free-Transform so you can manipulate the sloper photo (click to see larger image)

Pick any of the four corners of the photo layer (I chose the top right corner) Hover your mouse directly over the box shape and the mouse cursor will change to a double arrow. When you see the double arrow cursor, left click the mouse and hold, keep holding but don't move just yet, because you also need to hold down SHIFT, and ALT at the same time.

Now, while you're holding down SHIFT, ALT and the left-click of the mouse with the double arrow cursor showing DRAG the mouse outwards.

The photo layer will enlarge from the centre of the image (this what holding down ALT does) while maintaining the correct portions (holding SHIFT maintains the proportions) and it's the mouse dragging that actually increases the picture.

Don't worry if your photo layer goes beyond the edges of your document, we'll re-position it next, just get it to roughly the size of the background.When you're happy enough with the enlargement, let go the mouse first, then let go of shift and alt. The frame will still be active/visible and that's what you want.

using the Free-Transform frame, Enlarge the sloper photo by clicking and dragging. Hold SHIFT at the same time to keep the proportions to the correct scale. (click to see larger image)

To align the graphic properly, with your mouse positioned anywhere inside the Free-Transform frame, left click, hold and drag the enlarged image to the centre of your document. as pictured below. 

Position the enlarged sloper photo in the centre of the document (click to see larger image)

Although closer to the size I need it, the graphic still doesn't match the precise size of the background document. So with the Free-Transform frame still active I need to repeat the dragging the image out by the corner, while holding SHIFT and ALT. (You don't have to hold ALT, but you MUST hold SHIFT)

When you're happy with the size, press Enter and the Free-Transform frame disappears.

See below, I have aligned the cutting board measurements in the photo to the edges of the document, ensuring I have a full-sized 1:1 version of my Bodice Back Sloper. 
Note how the top left corner of the cutting mat layer aligns with the Photoshop Rulers point Zero, Zero, and the top right, and bottom right corners of the mat and wooden ruler, align again with the Photoshop Ruler of 30cm.

Sloper photo has been centred and enlarged to the point the measurements in the background are equal to the dimensions of the Photoshop document. (click to see larger image)
This full-sized image becomes the basis to scale up a vintage sewing pattern, by having a reference to your key measurements which you have to match in order to fit you, for example, shoulder width, arm scythe etc

Something which I recommend is adding in a guideline to indicate the waistline if it's not marked on your Sloper, as it isn't on mine. Here's how:

Let's say I know that my waistline is 35cm down from the back of my neck, that's the lowest point on the neck hole curve on my sloper. But I can't just put a waistline down 35cm from the top of my document, because I can see the neckline is 5cm down from the edge of the page, so I need to make my waist guideline at 40cm down from the top edge of the document.

To do this, go to View > New Guide 

Add a New Guideline (click to see larger image)

and enter in the HORIZONTAL distance required in the pop-up box, as pictured below.

Enter the correct horizontal distance in the new Guide options (click to see larger image)
A guideline will appear:

This guide serves to show whereabouts the waistline is. (click to see larger image)

Now save your document as a PSD - Photoshop document, and repeat this procedure for all the Sloper bodice pieces, creating a full-sized graphic for your front, back and sleeve.

Next week in Part 3 I'll show you how to take an Historical sewing pattern and scale it in Photoshop, and in Part 4 I'll show how to take your sloper and pattern and merge them together to create a final printable pattern that will fit you.

Please feel free to ask questions :)


  1. Anonymous12:27

    I am going to make a sloper to give this a go. Great clear instructions

    1. Good on you! Please let me know if you find I've missed a step, or anything is unclear. All the best :)