diff --git a/src/misc.js b/src/misc.js
index 87ba8d85..181069e7 100644
--- a/src/misc.js
+++ b/src/misc.js
@@ -73,7 +73,7 @@ export function formatHash(b, title) {
 export function hashToHex(b) {
     const a = new DataView(b.buffer, b.byteOffset, b.byteLength);
     let S = "";
-    for (let i=0; i<16; i++) {
+    for (let i=0; i<a.byteLength / 4; i++) {
         S += a.getUint32(i*4).toString(16).padStart(8, "0");        
     }
     return S;
@@ -198,7 +198,7 @@ export function stringifyBigIntsWithField(Fr, o) {
         });
         return res;
     } else if ((typeof(o) == "bigint") || o.eq !== undefined)  {
-        return o.toString(16);
+        return o.toString(10);
     } else {
         return o;
     }
diff --git a/src/powersoftau_export_json.js b/src/powersoftau_export_json.js
index 0200002d..60a0fccc 100644
--- a/src/powersoftau_export_json.js
+++ b/src/powersoftau_export_json.js
@@ -29,7 +29,7 @@ export default async function exportJson(pTauFilename, verbose) {
     const pTau = {};
     pTau.q = curve.q;
     pTau.power = power;
-    pTau.contributions = await utils.readContributions(fd, curve, sections, true);
+    pTau.contributions = await utils.readContributions(fd, curve, sections);
 
     if (sections[2]) {
         pTau.tauG1 = await exportSection(2, "G1", (2 ** power)*2 -1, "tauG1");
diff --git a/src/powersoftau_import.js b/src/powersoftau_import.js
index 188e67ba..bc2624cd 100644
--- a/src/powersoftau_import.js
+++ b/src/powersoftau_import.js
@@ -41,10 +41,10 @@ export default async function importResponse(oldPtauFilename, contributionFilena
         ({contributions, power} = jsonObj);
 
         // get curve from q
-        const qs = Scalar.fromArray(misc.hex2ByteArray(jsonObj.q), 256);
+        const qs = Scalar.e(jsonObj.q);
         curve = await getCurveFromQ(qs);
         // no points (sections !)
-        // Convert contribution hashes to Scalar
+        // Convert contribution hashes 
         for (const i in contributions) {
             contributions[i].nextChallenge = misc.hex2ByteArray(contributions[i].nextChallenge);
             contributions[i].partialHash = misc.hex2ByteArray(contributions[i].partialHash);
@@ -55,7 +55,6 @@ export default async function importResponse(oldPtauFilename, contributionFilena
             contributions[i].betaG1 = misc.hex2ByteArray(contributions[i].betaG1);
             contributions[i].betaG2 = misc.hex2ByteArray(contributions[i].betaG2);
             contributions[i].key = deserialiseKey(contributions[i].key);
-
         }
 
     } else {
diff --git a/src/powersoftau_utils.js b/src/powersoftau_utils.js
index f7bf4cb1..d9db096d 100644
--- a/src/powersoftau_utils.js
+++ b/src/powersoftau_utils.js
@@ -160,7 +160,7 @@ export async function writePtauPubKey(fd, curve, key, montgomery) {
     await fd.write(buff);
 }
 
-async function readContribution(fd, curve, formatted = false) {
+async function readContribution(fd, curve) {
     const c = {};
 
     c.tauG1 = await readG1();
@@ -171,10 +171,6 @@ async function readContribution(fd, curve, formatted = false) {
     c.key = await readPtauPubKey(fd, curve, true);
     c.partialHash = await fd.read(216);
     c.nextChallenge = await fd.read(64);
-    if (formatted) {
-        c.partialHash = misc.hashToHex(c.partialHash);
-        c.nextChallenge = misc.hashToHex(c.nextChallenge);
-    }
     c.type = await fd.readULE32();
 
     const buffV  = new Uint8Array(curve.G1.F.n8*2*6+curve.G2.F.n8*2*3);
@@ -184,9 +180,6 @@ async function readContribution(fd, curve, formatted = false) {
     responseHasher.setPartialHash(c.partialHash);
     responseHasher.update(buffV);
     c.responseHash = responseHasher.digest();
-    if (formatted) {
-        c.responseHash = misc.hashToHex(c.responseHash);
-    }
 
     const paramLength = await fd.readULE32();
     const curPos = fd.pos;
@@ -231,7 +224,7 @@ async function readContribution(fd, curve, formatted = false) {
     }
 }
 
-export async function readContributions(fd, curve, sections, formatted = false) {
+export async function readContributions(fd, curve, sections) {
     if (!sections[7])  throw new Error(fd.fileName + ": File has no  contributions");
     if (sections[7][0].length>1) throw new Error(fd.fileName +": File has more than one contributions section");
 
@@ -239,7 +232,7 @@ export async function readContributions(fd, curve, sections, formatted = false)
     const nContributions = await fd.readULE32();
     const contributions = [];
     for (let i=0; i<nContributions; i++) {
-        const c = await readContribution(fd, curve, formatted);
+        const c = await readContribution(fd, curve);
         c.id = i+1;
         contributions.push(c);
     }